How to open a browser using vb.net

Hi All
I need to make a login module in vb.net.
when user loged in the application will be minimized into the tray icon.
and by right clicking on the icon the menus logout search and home should appear.
I have done this part successfully but the another part in which
if somebody click on the search menu it should be redirected to the url
like http://www.abc,com/abc/[email protected]&fm=search.
similarly if somebody clicks on the home menu it should be redirected to
http://www.abc,com/abc/[email protected]&fm=home.

in the url [email protected] will be the userid.
I am newbie in .net
please help me to solve my problem.

Thanks.