Not sure what others recommended in your previous post, but I'd say for sure get a medical evaluation to be sure everything is okay.
If he's a late bloomer, from everything I've read, it's not good to rush them along. Crawling on the floor is suppose to be very important for a child's sensory development and immune system. If he wants to crawl I've read it's okay for him to do so. If he wants help getting around, then that's okay too. I can't remember for certain, but I think I remember reading this in a Dr. Sears book, or maybe it was the "What to expect.." series.
If you guys are getting tired, try a door way jumper. He will build up incredible leg strength and build up the necessary muscles and confidence in no time to help him walk.
I know they have fallen out of popularity because of safety concerns, but a good old faashioned walker is good for giving him mobility and support as he strengthens those legs. Just be sure to keep him away from steps.
My kids loved both of these activities..especially the doorway jumper. In my opinion the new stationary jumpers aren't as nice as the old fashioned door jumper. My oldest didn't get to use the new kind, but the youngest did, and he by far preferred the doorway jumper because they can get a real workout, jump higher, walk around, swing, and just have way more mobility.
I recommend Fisher Price's stationary jumper and Graco's doorway jumper with the bumper tray. The tray protects your child from getting bumps as they bounce around. The jumpers without the tray offer no protection between your child and the doorway, so you'll have to watch them very closely.
Last but not least, there are tons of pushtoys on the market, where the child stands behind a large truck, car, or wagon type toy with a tall handle in the back for support as they walk. This might be an option too. Some of them can be a ride on toy when they're not using it as a push toy. My boys have a giant Thomas the Tank Engine that's both a ride on and push toy, and they love it.
Hope this helps.