You can locate the different account types by scrolling through the Market Watch pairs/instruments. If you can't see them/any, right-click on a pair/instrument and click on the Show All option.

Standard Pairs     

$7 Commission, majors pairs have a medium spread. 

Pro Pairs (.pro)    
$8 Commission, majors pairs have a smaller spread. 

VIP Pairs (.xtr)
$12 Commission, major pairs have even a smaller spread than Pro Pairs, 25k minimum deposit.

Var Pairs (.var)

$0 Commission, major pairs have a higher spread. 

Mini Pairs (.mini)

$1 Commission, smaller lot sizes (1 lot = 1000).

Mini Pairs (.Mini)

$7 Commission, this is only valid for Indices.

Big Pairs (.big)     

$10 Commission, larger contract sizes, depending on the pair selected.

*The above commission stated for Pro pairs is excluding XAUUSD.pro which holds a commission fee of $10, as it falls under the Metals category. Different account types are only available for Forex and certain other symbols.