I'm using a Belkin 7010 wireless card which uses the RT2500 chipset.
My setup was straight forward. I downloaded the driver from
http://rt2x00.serialmonkey.com/wiki/index.php/Downloads and followed the instructions in the readme file within Modules
Build Instructions:
====================
For 2.4 or 2.6 series kernel:
a. $tar -xvzf rt2500-x.x.x.tar.gz
go to "./rt2500-x.x.x/Module" directory.
b. $make # compile driver source code
c. $make install # installs kernel module driver
I didn't bother with the raconfig utility.
The only other thing I had to do was add "/sbin/dhcpcd ra0" to /etc/rc/d/rc.local.
I didn't copy the RT2500STA.dat file to /etc/wireless/RT2500STA.
I was starting with a clean install of Slackware which had only had a wired connection via built in ethernet configured to download the driver from serialmonkey.
lspci
09:00.0 Network controller: RaLink Ralink RT2500 802.11 Cardbus Reference Card (rev 01)
iwconfig
ra0 RT2500 Wireless ESSID:"xxxxxxxx" Nickname:"Slack"
Mode:Managed Frequency=2.427 GHz Access Point: xx:xx:xx:xx:xx:xx
Bit Rate=54 Mb/s
RTS thr
ff Fragment thr
ff
Encryption key
ff
Link Quality=84/100 Signal level=-59 dBm Noise level:-193 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:49 errors:0 dropped:0 overruns:0 frame:0
TX packets:49 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:11124 (10.8 Kb) TX bytes:11124 (10.8 Kb)
ra0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
inet addr:xxx.xxx.xxx.xxx Bcast:xxx.xxx.xxx.xxx Mask:255.255.255.0
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1421 errors:0 dropped:0 overruns:0 frame:0
TX packets:1482 errors:0 dropped:0 overruns:0 carrier:0
collisions:26 txqueuelen:1000
RX bytes:1289281 (1.2 Mb) TX bytes:271700 (265.3 Kb)
Interrupt:10 Base address:0xf000
I'm using Slack 10.2 with the 2.4.31 kernel
HTH