I mentioned this in your other thread, but I can't recommend
Man's Search for Meaning highly enough. In my opinion, you've got nothing to lose by reading it because even if you end up absolutely hating it, it's a short read [img]/images/graemlins/tongue.gif[/img].
The Conquest of Happiness by Bertrand Russell
Learned Optimism and
Authentic Happiness by Martin Seligman
The Road Less Traveled by M. Scott Peck
also, a good bit off-topic but still related to psychology and the pursuit of happiness, another one I can't recommend strongly enough is
Flow by Mihaly Csikszentmihalyi. Great great book.