What do you mean a couple of Polkas? How about :

Siege of Ennis/Dashing White Sergeant/Scarterglen/The ballydesmonds (all three)/Denis Murphy's/The 40 pound float.

And don't forget the slides.

O'Keefe's (two of them) /cock o' the north/sweets of may/denis murphy's.

If you ever come across a book called "Begged, Borrowed and Stolen" an Australian publication that seems to have been copied an infinite amount of times, you'll get about 100 tunes that are used fairly extensively. I have heard that it is floating around in the States, so someone at a session may have it.

the best way to learn is to turn up, listen, ask for the names of tunes that are popular with the players, and then learn them either by ear at the session, by taping sessions, getting the sheet music (and there are about 8,500 tunes in ABC format on the web of which at least 5000 must be Irish/Scottish) or a combination of all three.

Gee have fun!!!!

BB