Ok i want to make a wall just a bland colour like light blue.
is their a paint option in hammer so i can just apply a colour to a wall rather than having to just go for a default texture

nope, you have to make a texture.

im a class A noobie at this, how would i make a texture exactly?
how does it get imported into hammer?

when a user plays this level with custom textures, do they have to download them, or are they all held i nthe compiled map file

This might help:

http://developer.valvesoftware.com/wiki/Creating_a_Material

i just ran thorugh those steps but when i take the tga and try to convert it via the command prompt, it says the file is bogus, and i get a text file as an output (empty)
any suggestions?
or can someone send me a millitary green texture (ready for use in hammer) similar to the colour of the front of the building?
http://www.ramsburyatwar.com/media/bob11.jpg

caboose, what image editing software are you using?

If you are using Photoshop, Nem made up a import/export plugin for Photoshop, very,very, handy.

http://nemesis.thewavelength.net/index.php?c=155

I use a lil' program called VTFEdit to create the .vmf file. Also very handy and time saving. Nem also made this (this guy is amazing)

http://nemesis.thewavelength.net/index.php?c=149#p149


:)