Below is a list of prospects the Steelers have met with at the combine or who they are linked to by a source....feel free to add more if you hear the information...
OG Jonathan Cooper NC
RB Montee Ball Wisconsin
WR Robert Woods USC
DT Jordan Hill PSU (He told reporter Steelers are interested in him)
LB Michael Mauti PSU (Wexell says Steelers are interested in him)
DE/OLB Ezekial Ansah BYU (As previously mentioned on this site)
FS Kenny Vacaro Texas (Wexell reports Steelers will meet with him)
OLB Jarvis Jones Georgia (Dulac speculates Steelers are interested in him (no kidding))
WR Keenan Allen California (Dulac speculates Steelers are interested in him)
All the info I have seen so far.