Vader9900 has really good little set pieces on ebay! He has dope dio displays too!
Marauders is the bomb someone else mentioned it, johns the best ships super fast!
Like dan said just everywhere! I have been collecting dio pieces for about 10 years now. I even buy other toys I dont want just for there pieces! Lol antique shops are a great place as well! some of the best pieces are found in the cheap prankster section at stores like spencers. Ive found a toilet key chain, the tubes and pipes I use for dios are actually build your own straw tubes just be creative! I great place for Ideas is stormthecastle.com as well as everyones pictures here!

Desks, lockers and foot lockers? Hmmm....lockers, you need to go with Marauder or hope to get your hands on the PTE bunk/locker sets. As for footlockers, I've never seen fully functionaly 1:18 scale ones, but there are molded plastic ones with the 1:18 scale MASH set....you can sometimes find it on ebay...but it's pricey...usually goes for about $70 - $120...on the upside it has tents, footlockers, chairs and mess hall tables along with hospital beds! As for desks, I say make your own or try doll stores that sell doll house supplies...if not, look for Lil Bratz stuff on ebay. It's scale is close enough to GI joe to pass...I have like 7 of their sets! Sometimes, you can go into dollar stores and they have dollhouse furniture cheap! Or you could try scoreing some Playmobil sets...the Office furniture set was about $6.99 on ebay (and probably the same amount for shipping!)

hope that helps!

Ok, just got a shipment from Marauders. Got some weapons racks, and a couple bunk beds. Building a couple of "standing" tables from smokeless tobacco cans. Also ended up with a crap load of weapons. Very nice indeed. Thinking of making some footlockers out of foam core and popsickle sticks. This should be interesting.
I have one more question, what seems to be best for adhereing items to surfaces. For years Ive used Elmers school glue, because it dries clear, provides stability, and is completely removable. Is that alright or is there side effects I don't know?

I will try to post pics when I get far enough to reveal it.

Check your local thrift stores, like the Salvation Army or Goodwill. I have hit dio gold there on numerous occasions. Another good place is Micheals, they have wooden desks and cabinets. Playsets for girls are great places for furniture alse, but they tend to be pink and blue and yellow. Some paint and they look great. Check my how-to thread and others for ideas on how to turn old junk into decent stuff.

Ok, So Ive begun making a mock-up dio. Im creating a small barracks room as a start. The biggest problem Im having is adhesive bleed-through. Can anyone recommend a fix. Would it be easier to use a different adhesive, or should I use heavier paper?

I would suggest heavy card stock paper or foam board! i honestly only use hot glue now adays for all my sets! mostly because if you mess with it enough it can come apart easier than ther glues and it has a tendency to stick to everything. I also like it because I have been able to heat up things that I ahve glued an they came apart because I used hot glue. everyone has there own methods that work you might just have to play with some stuff and see what works! Im always trying to stretch a nickel and the 99 cent store carries hotglue lol! as well you can glue your sets and then paint over the bleed through unless your printing the background or walls?