Assuming you mean cash ISAs, you can only put �3600 into cash ISAs in any one tax year.
If you had a cash ISA in 2008/09 into which you paid money, you can keep that ISA and then open a new one with someone else and pay in �3600 on or after 6 April 2009. Or of course you can pay the �3600 into the same ISA as last year after 6 April. But you can't do both.
Look at Martin Lewis's site
http://www.moneysavingexpert.com/savings/ISA-g uide-savings-without-tax
Is that what you are asking?