How to make wallpapers and publish it on the web as your blog?

Wallpapers are just pictures so a program like Photoshop would be a good one.

http://www.adobe.com/products/photoshop/index.html

Photoshop can cost a bit of money if you are not doing too much with the images.

CorelDraw make Paint Shop Pro

http://www.corel.com/

which is a slightly lower priced program with a little less functionality.

If you are looking for a free picture editing program you could use Gimp

http://www.gimp.org/

Then you need an image hosting page like imageshack and imagevenue

http://imageshack.us/

http://imagevenue.com/

There are also other image hosting websites that will let you upload one picture at a time without the need for membership or payment. They normally have a bandwidth limit though.

You can use any graphics softwares for creating wallpapers.

Adobe Photoshop may be the most used one. GIMP, PhotoPaint,... even Microsoft Paint can be used for this.

Use a digital camera... you can use those pictures as wallpapers without even modifications.

Think you need html, copy one from a that uses it then you could edit it