I have one haven't fired it in a while seems to have lost power and accuracy. Would there be anybody that knows how to take them apart and rework them. Any help would be appreciated. Nick

You may have a bad seal. There's a ton of info on the net about building spring compressors and changing springs and or seals your self. Be VERY careful working around that mainspring. It's very powerful and capable of hurting you. Here's a place you can order parts.
http://www.airrifleheadquarters.com/page/page/251488.htm

If you're not mechanically inclined, there are multiple places you can send the rifle to have the work performed for you.