Parks & Wildlife uses some double-speak as it relates to feral hogs. They say you don't need a license to hunt "depredating feral hogs" (which is every loose pig in the state) but then say the special non-resident license will let you hunt exotics including feral hogs. I'd personally err on the safe side and plan to buy the ~$130 5-day license.

Unfortunately I can't make any recommendations on outfitters. We hunt them on our lease, when we can find them, or more often on ranches owned by family & friends that have become over-run. My most fruitful hunts are in Brazoria County (about an hour south of Houston) but I'm sure there are many, many places that would yield as many or more pigs.

I'd suggest figuring out the type of hunt you want (sitting in a stand, horseback with dogs, ATV with dogs, etc.) or the area of the state you want to hunt and then try some internet searches. There's really no shortage of pigs or people guiding hunts for them.