Skins are still available for offline viewing, Eagle. Check out the HTC approved skin pack (on the downloads page). This is updated once a month and contains all skins that would otherwise download while online. It's fairly large and was last updated earlier this month.
The skin pack will automatically install itself. The skins are in a .res format and cannot be altered.
Also, you can browse a player made site (created by Lucull):
http://www.ah-skins.comThese skins must be installed manually in your //HTC/Aces High II/skins directory by creating seperate folders for each skin. The folder must contain an object.txt (where 'object' = the name of the plane). This file contains a one line description of said skin. Then copy over the actual skin bitmaps to this directory.
The skin folders must be numbered sequentially. For example, if you have multiple 109G2 skins, the folders must be: //skins/109g2
1 for the first skin, //skins/109g2
2 for the second, etc.