only left click on the mouse?

control-click has always been apple's right click. Apple does have a few desktop mice that acknowledge the fact we live in a multi-button moused world.

 

You can also go into your keyboard and mouse settings and enable a two finger right click on the trackpad.

 

Enabling the two finger click is huge. It is in System Preferences. It allows you to put 2 fingers on the pad, click, and that will bring up the right click menu.

 

other mice

You can (and I would) get another mouse to use with your laptop. Personally I hate using the pad when a wireless mouse is nearby. The lack of right-click bothers me a LOT less. If necessary I recommend Microsoft's Notebook Optical Mouse 4000. The design is nice and it is picked up by Mac's quickly and flawlessly. I love that the wireless USB link fits into the bottom of the mouse and removing it turns the mouse on. I use the cool super mouse for my iMac and the Microsoft mouse for my ibook. I switched to the wireless mouse halfway throught this message. (pointless but it prompted the "quickly and flawlessly" comment.)

 

Ah, so you have an ibook... he is talking about the macbook... which supports 2 finger scrolling, 2 finger secondary clicking, and is larger to boot.

I say hold off on the mouse purchase until you absolutely are sure that you cannot live without it (which I usually cannot in Windows). IMO, the trackpad on the MacBook and MacBook Pros are the best in the business.