Novice question – Page Layout

Hello all,

I am new to WP so please forgive my question. I want to create a fairly simple site. It must have the following blocks in this order:

1. Header
2. Horizontal menu
3. Slider
4. 3 columns, each containing a thumbnail (together with some text either below the picture or as hovered semi-transparent caption). The thumbnails should link to a page having galleries, text etc.
5. Footer

However I notice that the theme I am using (created with Artisteer trial, as I will undoubtely switch to paid WP themes after a while), does not give me the ability to have 3 columns, only each widget below the other.

So the question is: Is the layout I describe possible to be created with WP (and/or free plugins)? Or do I have to purchase a commercial theme (or a plugin like ‘
Sidebar & Widget Manager’ to achieve this?

Please let me know if I am not being clear enough.
Thank you