I thought SQL::Abstract was a good idea, but when I wanted to do something complicated it was not so easy. It was easier to read write a complicated SQL statement rather than figure out the syntax to make a SQL::Abstract object. It is cool idea though.

Class::DBI I also felt like it was neat idea, but when I needed to do something complicated it was not so easy anymore. For something like your address book though I would consider using it.

DBIx::Class was the same concept as Class::DBI and after fooling around with Class::DBI for while I just did not want to bother figuring out DBIx::Class. It also did not have all the modules that Class::DBI did either which I felt limited its usefulness.

I ended up sticking with plain DBI and I cannot say I really have had any problems with it.