As mentioned in other blog posts, I am not a designer, so yes, one could say I'm a design noob.  I recently created my own original theme for my Blog (as opposed to just porting a Wordpress theme to Graffiti), and I found some sites that were a big help to my endeavor.  I hope others find them useful:

1. Stripe Generator:  A generator to make a striped tiled wallpaper.  I used it to make the background on this site.
2. Tartan Maker:  Similar to the Stripe generator, this one makes tartans.  I played with it for a while - it was fun!
3. Background Patterns:  This is a simple generator where you can make some antique-looking wallpaper. 
4. GC Textures:  These guys have a huge selection of textures for use in backgrounds - anything ranging from bricks and stone to monkeys.  They do have a daily download limit, but I didn't have a problem with that.
5. Patterns and Palettes:  Colour Lovers pallets and patterns are really awesome.  They offer patterns with matching color pallets.  You can download them for many different applications - even Gimp.  There's some excellent work here!
6. Kuler Color Palettes:  If you're design-blind, as I am, this is a great site where you can see a collection of great palette selections.  The themes are for use in Adobe apps, but I cheat and use ColorCop to grab the color values and work with them in my own graphics editors (Gimp and Paint.Net)
7. CoolText Text Images:  I used this to generate my own site title image.  You begin with a logo style, but you can then change the fonts, make the backgrounds transparent etc.  It will allow you to download the image as .gif, .jpg, .png etc.  They also have a similar feature for buttons, and they also have a huge font collection.
8. Interactimage Font Image Generator:  Their interface takes a bit of playing, but this is a pretty cool site where you can create banners, or e-cards playing with fonts and dingbats.  You can flip and layer them and play with colors and a few other editing tricks also.
9. Image After:  They have almost 20,000 free textures and images.  Most of these are in high resolution and are perfect for turning into header images.  They also have a color finder feature where you select a base color and it searches the images to find ones that match your choice.  I found the image for my header here; I just cropped the section of the image I liked and resized it to be a header size.
10. Bullet Madness:  This is an offering of 200 bullets arrows and icons to be used in lists and other areas where tiny icons are needed.  Make sure to check out the rest of the site - there are great CSS references and other goodies here as well!

The free applications I used to monkey with my graphics were Paint.Net, Gimp and Color Cop.  Those are absolutely invaluable to me!  Please post any other such tools in the comments section of this post if you know of others!