Where to sound deaden?
 

I want to sound deaden my trunk(nissan altima)?

1) Where are a few good place's to check out?

please keep in mind I will be using my own sound deaden product

There are plenty of places that carry all the good sound deadeners. However, I noticed that you wrote that you're using "your own" deadener. If this means what I think it does, you will be disappointed. I assure you there are ALOT of us that did the same thing and now know we should have saved the $60 we wasted on the roofing material and used it towards a proper deadening product.
If I'm wrong and you indeed have/plan on using a decent sound deadening product (B Quiet Ultimate, Raamat BXT, Dynamat Extreme, Damplifier Pro, etc.), then you'll find both your back dash and trunk lid love to buzz. Basically any thin gauge metal will resonate fairly easily. Oh, and your license plate...a perennial offender!!
Happy install.

I used butyl patches and it worked amazingly. I had to use alot of them tho since they are small patches. It actually came in handy tho because there were alot of tight spaces i had to get into to cover. I put it on the trunk walls since they are a bit of a thin sheet metal and tend to flex easily, i also covered the trunk lid since it was rattling a bit. It worked very well, although i need to cover one more spot on the trunk i realized i missed. It was a very noticable change since where ever i put the sound deadener it was fine now, other than the one spot i missed. When i push on the spot i missed it actually kills off alot of sound outside of the car. I plan on fixing that today, as soon as the rain dies down a bit.
I had alot of people tell me not to use "home remedies" because they wouldnt work. This wasnt exactly a "home remedy", but not a typically used product. However it IS used in factory sound deadening from car manufacturers around the world, so i already knew it was going to work a bit.
I do believe if i had used dynamat it would have worked better, but considering the price difference it would have made, i am glad i went with this.