Affiliates of online stores: do you really need to parse all XML yourself?

Question

Electronic commerce

Hello.
There is a site, the site has, among other things, a database of books with ISBNs and other fields. I would like to display affiliate links to stores next to each of them. Approximately how it works here: www.livelib.ru/book/1000476637
The question is obvious from the topic: “Really?” Is it really for my modest site with a total planned income of 2 thousand per month from all affiliate programs, I need to write a service that will load XML from a bunch of sites and 1 GB (in the case of ozone) each, dig them, put them in the database, follow behind all the format changes of all a dozen stores, just so that a random person can click on a link?

Is there such a service, well, you understand, so that there is an ISBN or a name - once, and it will answer you with an XML store, name, price, availability - and so on for everyone, and so that it is alive and monitors changes in catalog formats?
Who faced — share experience.

PS So far I have found only www.findbook.ru/ from free ones - better than nothing, but there is no XML there - you need to send requests by post or get, receive HTML in response, parse it, which is not very correct.

Answer 1

> will load XML sites from heaps of 1 GB (in the case of ozone) each, dig them, put them in the database
You say it as if it is very difficult in a normal language with sane libs.

Answer 2

> Is there such a service, well, you understand, so that there is an ISBN or a name - once, and it will answer you with an XML store, name,
> price, availability - and so on for everyone, and so that it is alive and monitors changes in catalog formats ?
And what profit would such a service provide this information?

Answer 3

Do you really need to write CODE!?!?