Linuxmint main edition is using a newer kernel then the LMDE release. I have no personal experience with your specific card but I always consult http://wireless.kernel.org/
when dealing with wifi-not-working. They are usually very helpful and newuser-friendly. They have a active mail list and also a irc-channel on Server: irc.freenode.netChannel: #linux-wireles
I suggest you look at the docs first and then ask in the IRC-channel. Use Xchat which is included in LMDE.
AMD Quad-Core, 4GB RAM, ATI HD3650silent, 33TB harddrive Laptop:
Lenovo Thinkpad x201, Intel core2centrino P9600, 4GB RAM, 750gb