Make a handbill and send it round to the functions manager at all the venues that do receptions. These people get asked to recommend music, and are usually glad to keep contact details, so they don't have to go looking when someone says "Can you find someone to play celtic music?" or whatever.

Look in the phone book for agencies offering to provide music for weddings. They may charge a percentage, but 90% of something is better than 100% of nothing.

If it was your wedding, and you didn't have musical friends, how would you find the music you wanted? Wherever you'd go for the info, your friend should be there.

All the best,

Andrew