Hello.
I want to send a string (for example ABCDEF12345) that created by AVR (ATMEGA32) and send it to the web (My website) by SIM900 (GPRS) and that string shown on a web page.
The original poster in this thread didn't receive a reply, this should tell you something, you can't expect someone else to do all the job and hand you the code (unless you want to hire someone)
This is something that you have to do in order to learn so instead of asking for the code start writing your own, it's the only way to learn.