*Loan,banking and credit>>>credit line

Is there a credit card company that will give me a line of credit when my credit is not that good?

need an instant line of unsecured credit.

I'm sure there is, however, the interest rate will likely be above 20%

go to your bank. easiest place to get a credit card. noone else will approve you for anything.
My credit was a bit sketchy and I wanted to improve it - Capital One issued me a credit card.

Read the fine print!!!
There are Banks that will let you have a secured VISA card. B of A is one of them. You don't need good credit to get one - you deposit an amount, for example $500 into the bank and then they will give you a VISA with a $500 limit. Interest rates should not be that high - you are borrowing your own money. See if this credit card will be reported to the credit bureas so it will raise your credit score if it is reported to them (assuming you pay it on time)
Try your bank. Otherwise, Providian, Household or Orchard Bank. You'll pay through the nose in interest in fees though.
cross country bank, aspire, providian, capital one, orchard bank...you can also try your local bank or credit union if you're a member of one
search bad credit credit cards in your search box. There orchard bank should come up. They helped me re-establish my credit and there are no fees.