A couple of things to try,
Make sure any firewalls, have let through the IP addresses of your two laptops.
Make sure they are both in the same domain.
Make sure you can ping the one laptop from the other.
Make sure you have file and printer sharing installed.
Make sure that you have shared a folder from the one machine, to connect to on the other.
If you are using XP on either machine, and you do not use passwords, then you will need to enable blank password network sharing, post back is you need this.
If all of the above are ok, then just try to connect a shared drive to your other laptop, by right click my computer, and map network drive.. then just type.. \\laptopname\sharedDrive
If any or all of the above does not make sense, then post back and I'll go through one step at a time.