What's up rik... That's great advice. A systemic application of neem is said to be very effective. I water in menial amounts of neem whenever I remember or whenever the pests remind me...
Outdoors I have had success in planting "trap" plants (mostly basil) and also plants to attract beneficial predators (dill, marigolds, lavender, etc.). I've had success with these plants in separate pots right next to each other but it seemed to be more effective when I planted them in the same pot.
My tomatoes usually get their asses handed to them by fungi but if I take care (not just let them go) they hold off til I can harvest most of the goodies. Pests are (usually) kept in check by the dozens of other plants in the vicinity of my maters housing predators.