what are you having problems with? vocal levels? overall mix levels? both?
for Rap vox I usually strap on 1 compressor and 1 limiter, my current compressors of choice is the Ren Comp which goes first to control the dynamics, then I use the UAD LA2a in limit mode to catch any peaks...eq is so program dependant all i can say is roll off about to40-50hz and high shelf around 12khz and up..after compression.
For the overall mix, compression and limiting and eq is the answer. I'm guessing your probably mixing in to much low end (thats usually everyone's problem who just started mixing hip hop) which eats up headroom, which then inhibits you from increasing the levels w/o the bottom distorting, so put a High pass filter @ around 20 or 30hz...but your gonna have to play around with it till it sounds good.