If your wifi card uses hostAP you can use the "master" mode to make it act as AP.
Search for a man page for "iwconfig" ex. ill need smthnk like:
iwconfig wlan0 mode master
+ ip forward to gprs
If you need more help on wifi/hostap just ask.. Ive setup lots of them for Athens Wireless Metropolitan Network.
-Tasos
PS: pgas awmn is waiting for you