The type of PCB material depends on other factors in your design... power handling, cost, weight, trace width, etc. Rogers is a big name in PCB materials, so take a look at their High Frequency Laminates. For a simple design, you can probably get away with FR4 to keep the cost down.
If by Track size, you mean trace width, that is a function of several parameters... type of transmission line, substrate thickness and dielectric constant. Microwaves101.com is a great resource for fundamental RF circuit theory.
Here is a link to their microstrip calculator: **broken link removed**
If you want a stripline structure, there are other calculators available to compute those numbers, too.
You can use online calculators to find the right width, like this one for example: **broken link removed**
I would advise to use the AppCAD freeware from Agilent: AppCAD