http://www.has.vcu.edu/mac/our_story/hall_of_fame/hall_of...
Hi R. - I googled VCU Hall of fame and came up with a page that has a link to a slideshow of a past event. To me it looked like the women were wearing party dresses but no full-length red carpet stuff. If you choose something along the lines of black tie Christmas party, you will probably be in good shape.
It did appear to me that they were dressed pretty conservatively. Not a lot of boobs or even bare arms for that matter so you might consider covering those tats for the evening. Formal events often have just as much to do with the tone of the event as with the dress code. There is always body makeup to cover for a night.
Since you dont dress up a lot buy something you can wear again and either dress up or down. Maybe consider finding your perfect little black dress - above the knee but no more than 4" above. If it has no sleeves or short sleeves consider wearing with a little jacket with some sparkle to dress it up. A shrug would probably look too formal for a short dress in my opinion.
A beautiful sparkling necklace can also add pizzazz to a simple dress as would a scarf and a pin.
Just some thoughts . . .