Stuff Jason Waltrip Has Done

They most certainly are comics, with the exception of Mekton II, which is an RPG.

Robotech II: The Sentinels, based on the unproduced second season of the Robotech TV series, began its run about 1989 and lasted about 80 issues. Eternity Comics printed it most of its run but when DC took over Eternity, it went on hiatus and was later resumed under the Academy label. Jason and his brother John, for the most part of the run, alternated the art work between issues: Jason would do one issue and John would do the next, and in the words of the Long twins of Heinlein's Lazurus Long books, "make it march". This began to end when Tom Mason left the writing job for the books and John took over, meaning Jason's portion of the artwork got greater and greater.

Metal Bikini was a short run comic, only six issues long. It had one run at Eternity and was later reprinted by Academy. It was basically a parody of the Japanese OAVs of the time, borrowing a little from MADOX-01 and Megazone 2-3 in its story and from Cream Lemon in its imagery...so to speak. The setting is a Japan that looks more like California, either today or the near future. The story revolves around a young woman named Kenji who aspires to be a fashion model. Her grandfather designs weapons for an arms manufacturer and his latest creation is an antigravity suit of armor with integral blasters...a technology that threatens to make both jet fighters and tanks functionally obsolete. A combination of errors (and a scheming General in the Army) force Kenji and the armor suit (stripped of its skin to become literally a Metal Bikini) into action.
A minor character, Yojo (the assistant/test pilot for Kenji's grandpa), is practically an older and more macho Rikk Oberf.

Amazon Gazonga originally appeared in Triple Action, and anthology comic printed by Eternity. Like Metal Bikini it appears to have been reprinted by Academy. Gazonga is a young warrior maiden from a clan in the pre-Columbian South American jungle. In her tribe, women rule and men are livestock. Her life changes when she falls in love with the boy she captures on her first raiding party.
Like Metal Bikini, Amazon Gazonga is heavy with sexual imagery and slapstick humor.

Mekton II is a role-playing game developed by Mike Pondsmith of R.Talsorian Games in the late 1980s. Both John and Jason Waltrip contributed mecha designs and some illustrations in the series; Jason provided the cover to the Roadstriker II module/supplement, as well as several of that book's transforming robot/car mecha (including one that looks suspiciously like Optimus Prime of Transformers).

Mekton II was eventually superseded by Mekton Zeta so the books in the preceding series are out of print and hard to find.

I tried to scan some pages last night and found that the zip tone that was used made the scans look horrible. Watch this space...

Thanks to pennyangelos for this site, which basically has everything you'll need to know. Sorry FPilot!