http://wiki.eqemulator.org/p?Play_Gu...etting_Started
Titanium and ROF2 are the recommended clients. Some might still use UF but I think most have moved on to ROF2.
The client you need ultimately depends on what server you plan to play on and they (their community) can point you in the right direction for where to get it. (Titanium can still be found on retail CD)