Copying sharePoint site from one developers pc and then restoring it in another developers pc is a very common task in a sharePoint developers life. The steps to do this are -
1. Open Command Prompt and Go to Program Files->Common Files->Microsofft Shared->Web Server Extension->12->Bin
2. next write - For site collection backup
stsadm -o backup -url <"URL name"> -filename <"file name with full path"> [-nositelock] [-overwrite]
3. Check if the back up has been successfully completed or not.
4. If yes, then create one web application from the central admin and note down the url of the web application
5. now, in the command prompt write -
For site collection restore
stsadm -o restore -url <"web app URL name"> -filename <"back up file name with path"> [-hostheaderwebapplicationurl] <"Web application URL"> [-overwrite]
6. now reflect necessary changes in the config files and start using restored site.