Impressions (
The Decorated Apparel and Promotional Products Resource) sounds like what you're looking for.
Forums are ahead of the print curve more often than not though
(joking aside if you
really want to keep up to date you need both - print will run official announcements that are given to respectable print sources before they turn up online, sometimes have better industry experts, etc. but print can be a bit of a dinosaur - without online community resources you'll be left behind)