There are a few good ones "out there". In no particular order other than Hometown son goes first. And as information only...
1st, our own Allstar... http://www.allstarcustomsonline.com/?p=gfoot
Blue Chip (Steelers Sideline) http://www.bluechipcustoms.com/index.htm
RL Customs... http://rlcustoms.com/index.php?cPath=21_28
No Steelers but lots of stuff
And forgive me, but Raven Customs has a great reference page for subjects at a glance... http://www.ravencustoms.com/basefigures.html
He hasn't done any Steelers customs though. Maybe he's upset.
And of course, the original... http://www.mcfarlane.com/toys/catego...?categoryid=26
where you can see the entire NFL series.
Lots of great work and ideas for inspiration.
If you go to Allstar's site again, there is an excellent depiction of one of the better Steelers memories... http://www.allstarcustomsonline.com/?p=pcp
If yinz find any more customs pages, please share.