I want to add online store features to my website. I am interested to get Instant Payment Notification (IPN) of the purchases which buyers will make from my website.
Which company can be good to provide me this information.

You can only get IPN through a credit-card transaction processing company, like iBill

Or Paypal if you're someone who really doesn't care about his customers.

Seriously, Ali, you're going to have to contact a proper credit card transaction processing company. And no, while PayPal does offer IPN, I refuse to acknowledge them as a proper credit card transaction processing company. Something about those $10.5 million class action lawsuits and an "API" which my six-year-old nephew could work with...

Anyway, iBill's a good one to use. www.ibill.com is the site. Here are a few others.
www.internetsecure.com (they're out of Canada but they do have international customers as well)
www.beanstream.com (see internetsecure.com); very easy API to work with, customer does not have to leave your site, people at BeanStream actually know their rear end from a hole in the ground.
www.worldpay.com
www.goemerchant.com

There are a bunch of them out there, with a myriad of different features. The best thing you can do is look at what you want to try and accomplish besides IPN (transaction volumes, if you want the customer to stay on your site, if you need them to provide a merchant account as well as transaction processing to name but a few.) Either transio, myself, or someone else could give you a much more educated answer if you provided some additional criteria; it'd help you too since you'd know exactly what you were looking for.

That shopping cart service provider is good, who provides Instant Payment Notification (IPN) of the payment received from buyers, to the merchant. www.ikobo.com is very prompt in providing IPN information to its merchants. Many of my friends have merchant accounts with ikobo.com and they appreciate ikobo's IPN service.

Ali Ghulam, another company which can satisfy your IPN requirement is stormpay.com. Now you can compare ikobo.com and stormpay and then can make a selection.

You gotta be careful with Stormpay though. I haven't used them personally, but I know a few people that have. Because Stormpay is usable on adult sites (specifically, for some reason, the escort industry), their chargeback method is more geared to the vendor than a standard merchant account.

Much like PayPal, the customer has to do more to prove that a transaction didn't take place or was fraudulent in some way than the same customer would with most payment processors and non-Internet merchant accounts. By default, burden of proof lies with the vendor, not the customer, and under most VISA/MC/other credit card agreements, the customer is at most liable for a small arbitrary figure ($50 is the usual number) in the event that a customer is proven wrong. (Side note: all those credit card insurance scams...I mean...ummm...additional credit card validation protection options still being telemarketed to the US, usually from Toronto-based offices, are not necessary purchases.)

In other words, be very careful with Stormpay. It's funny that way, and may well end up with the same issues PayPal has.

If you compare ikobo with stormpay you will quickly realize that stormpay has higher fees, smaller number of features and money comes (if they come after all) with a long delay. So, I don;t say to choose ikobo.com but this is a good alternative. ikobo's IPN system is great, I managed to make a very good anti-fraud system with it . Now I want to do something else with my database. I will tell you later. Ciao

nixdorf: how could you build an anti-fraud system using ikobo's IPN if they don't keep the user on the site? Anti-fraud systems are the responsibility of the provider, if the provider requires the user to leave the merchant's site to maek payment.

It depends on what filters or rules someone uses. Of course ikobo offers an anti-fraud system and in fact it's very strict. I sent a lot of documents in order to increase my limits, but the way the do the checking, manually, is reassuring for me. Not like paypal where all is done automatically and these way frauds can happen.

You saying that iKobo checks transactions manually to ensure against fraud?

I've seen you people mention ikobo here and I decided to post here as well, since I use them myself. So far it's been ok, haven't thought about any kind of fraud protection yet. Except what ikobo provides. You people started to get me a little worried, although I haven't had any kind of problems so far. I'll look into this.
My personal impression so far is that ikobo is a reliable service, at least that's how it was for me so far, I hope things will stay like this.

No, not the transactions. They manually check the documentation (ID) you send them when you want to increase your limits of sending and receiving money with your ikobo account. For me it is a plus. That's what I said.

There are four things that bother me about that (and from what I've read, it's a driver's licence and a utility bill):

1. What do people who don't have either of the items do? I never had a hydro or gas bill until last month, and I've only had a phone in my name for about 5 years. And what about those people who can't get a license?
2. How do we know the information isn't sold or otherwise distributed?
3. What exactly do they do to manually validate it? And what do they do in areas where FOIPOP may make it impossible to run a check on a driver's licence?
4. WHat exactly does checking this information establish? All you can do with a driver's license in Ontario, for example, is check to see that it's valid. That doesn't necessarily imply that the person who owns it has never committed a fraudulent act. The same thing goes with autility bill. Lots of criminals have utility bills (many of them high as they grow unofficial pharmaceuticals in their basement.)

Something smells like fish.

I recommend worldpay, i have used it for past 3 years and their services is excellent.