13 August 2010
For claiming cenvat credit you are required to produce the orginal invoice. So credit need to be taken if and only if you had received the invoice from the party.
If you had made the payment but the invoice is pending to receive then wait for claming the credit up to receiving the invoice
13 August 2010
Cenvat credit in case of service tax should be taken only after payment is made. and as rightly pointed out by vivekji u need to get invoice and then only u can take credit even if payment is made
in simple terms it is the payment or receipt of bill whichever is later