usually most people start by >

1. a pinball u remember from your younger years (if applicable)
2. something u have seen or played at a friends/family members house you like
3. something u see on the internet pinball data base

http://www.ipdb.org/search.pl

4. something someone reccommends to you.

What sort of theme do u like ?  sports, scary, cartoon, action, .....there is a pinball to suit every theme.