You don't need a licence to import (most) goods.
If you're importing from within the EU you can import most goods without paying anything to HMRC if VAT has already been paid on them in the country of origin.
If you're importing small quantities of goods from outside of the EU you can simply do the same as people importing goods for their personal use. i.e. ensure that the sender attaches a CN22 customs declaration to the package and pay the import duty, VAT and customs examination fee when the goods are delivered to you (or when you're sent an invoice, payable prior to the release of the goods).
Otherwise you need to submit form C88 to HMRC to declare your imports. It might help if you've obtained an EORI (Economic Operator Registration Identification) but it's not essential.
When submitting your C88 you'll need to know the relevant commodity code(s) for your goods, in order that the relevant rate of Import Duty can be assessed. That can be found on the Business Link website.
This guide, from HMRC, is a bit easier to read than some of their other stuff:
http://customs.hmrc.g...ntID=HMCE_PROD_008051
Chris