Where can i buy some sticky goo or whatever it is that holds the emblems on? I took them off to paint them and i got a double sided adhesive tape kinda thing but its way to thick.

A good bet would be something like rubber cement. You apply a very thin layer to the surface your applying it to and a very thin layer to the back of the emblem. Wait a few seconds so they get a little tacky and then firmly press the emblem on the surface. It will take a few hours to reach maximum strength but it should hold through anything you'll see on the road (including water). You can also rub off any extra cement.

Just make sure you prep both surfaces. Cleaning them thoroughly will create a much better surface. If you are really worried about adhesion ligthly scratch/score the contact surfaces to increase the surface area.

How were the emblems attached in the first place? Glued straight on, or held with double sided tape?

If you browse at Autozone or Pep Boys or a similar place, you should be able to find thinner double sided tape or adhesive that's meant to hold trim on.

Ken

Automotive adhesive tape, it's usually in the paint isle at autozone/checker your choice. Made by 3M it may seem a little thick but it's the best stuff you can get.

there is an emblem adhesive that works great as well
the double sided tape works, but it can be irritating to use because you have to trim it perfectly

http://www.autobodytoolmart.com/3m-plastic-emblem-adhesive-clear-08061-p-10392.aspx

edit: I have seen this stuff in auto parts stores in the spray paint/auto body area

you can try to use clear window sealant or rtv black. both seemed to work for me.