Iphone 3g screen replacement, what's with the adhesive.

So I replaced my screen on my iPhone and now realized that there is no adhesive on the back of it like there was on the back of the stock screen, where do I get this?

You can buy it on ebay. I see it for sale often.

haha sorry for the ignorance

Did you replace the glass& digitizer only?

We have design a replacement adhesive for this specific application. We are the only place selling them although we will begin to wholesale them to other dealers next week.
We spent a lot of time and effort working closely with 3M to find an exact match to the adhesive apple used and then designed a shape to fit the iphone frame perfectly.

More info here iPhone 3G adhesive

I recently cracked my iPhone 3G screen and was almost duped into paying Apple 199 until i found iPhone 3G Screen Repair: iPhone 3G LCD Repair: iPhone 3G Cracked Screen. They repaired my phone for me and had it back to me the day after they received it! I really recommend them.