Take the KBB price for your truck, then drop it 10%. Add 50% of the value of your add-ons, and thats a decent place to start asking from. Economy is definitely a buyers market right now though, so be prepared to go lower if need be!
Like Forrest said if you can hold out you can probably get a decent $$, the issue is finding the right buyer at the right time. Post up some pictures, I would like to have a mega cab, but I am too cheap!
I have always gotten the most money selling on ebay... I was getting offers for $15-19k for my '04 when I sold it... I threw it on ebay and got $25k for it.
I sold my 97 on there, and I was asking $2500 for it on the boards... couldn't give it away. I got $3300 for it on ebay
we sold my wife's POS 94? Altima on ebay... I was ready to take $300 for it, I threw it on ebay, and some lady came up from Austin and paid $2000 for it