I've worked with Ink Brigade twice to do various-sized runs of t-shirts for my company. They've totally rocked it both times.
Perhaps best of all, their pricing seems to be the best that I've seen locally. They also don't have any additional set-up or screen fees.
Their customer service is extremely friendly, helpful, and patient (on the first order, we probably spent a week or two just deciding what kind of shirt we wanted to use. They were totally helpful despite all our indecisiveness).
They have a wide selection of apparel that can be screen-printed, although not everything is available in a hurry. It'd definitely a good idea to order as soon in advance as you can to be sure that they'll be able to get all the shirts (or whatever) that you need. With our first order, we were on a quick turnaround and they weren't able to source the shirts that we wanted in time, but they helped up figure out a great alternative. The second time, we learned out lesson and ordered WAAAAY in advance. Unfortunately, their online catalogue is a real pain to navigate, especially if you don't know exactly what product you want to print on.
The printing seems to be good quality. I've washed one of the shirts that they've done a dozen times or so and the screen printing still looks as good as new.
They also offer free delivery in Portland (and sometimes the suburbs), which is a nice plus.