InDesign
InDesign is used by graphic designers to create brochures, magazines, posters, flyers, newspapers, and books. It is basically where documents and graphics are prepared to be printed. The book is composed in InDesign so you can manipulate the text.
You can find tutorials for InDesign here.
Photoshop
Photoshop can be used in a multitude of ways, and creating book covers is one of them. It can be a very powerful tool as far as layering and typography. It is mainly used for image manipulation.Adobe programs such as Photoshop are not cheap. When first starting out there are some free or fairly cheap editing programs that you can practice with.
Pickmonkey: This site is for free photoediting but if you want some of the extra features then it is $4.99 a month.
Photobucket: Free
Pixlr: Free
You can find tutorials for Photoshop here.
Programs
