Think most our hotspots have been mentioned. Last I've heard Goodwill (franchise* so rules vary by city/owners) has a mandate to all goodwill in town that they must send all computer equipment to the goodwill computerworks store which is the one mentioned (off the frontage of north 183 and just before Burnett). Unfortunate for the other stores but makes it a single stop to know if they have anything vintage. Prices seem to model ebay though :-( but once and a while something nice is there.
Pinballz arcade (N. Austin)/Pinballz kingdom (buda) are functional arcades catering to pinball and early games nut also newer titles scattered around. Most are for sale but IMO at "not interested in selling" prices (2.5x? Going rates). Game over videogames is one of our better retro and vintage game stores. A few locations scattered around town but also a little high on prices. The staff though are usually pretty knowledgeable gamers and enthusiasts though depending on age and location. They also line their walls with part of the owners collection or boxes of consoles. The north lamar/anderson location has a small area as their "museum". This is also who started hosting an annual "classic game fest" in town. Gamefellas .. one of Austin's early on used and vintage game stores. They tend to have more boxed console games than other stores which you'll find loose carts. I cant ever get a good vibe on staff though. One store seems to have the good geeks then two others have a teen thats listening to an ipad and seems disinterested but maybe thats changed. I don't know what the schedule is but on (some?) Saturdays there's a commodore meetup group that Bo Zimmerman hosts. Possibility to see what I advertise as one of the largest commodore collections in North America. There are also a few hacker spaces but I'm not that familiar nor a member so not sure about touring those.