Remove My Transaction, Catalogs, Transaction in Process links

Hello everyone, need your help again:

I have a requirement to change main page to have Transactions tab with Searching capability and Check Backorders link only (remvoe My Transaction, Catalogs, Transaction in Process links and remove Products tab and New Transaction tray). My question is

Where are My Transaction, Catalogs, Transaction in Process links located (in which file)? Can I easily remove them?

Please advise.

Thanks, Jin