Can a condo association file a lien with the county clerk without entering a judgment in court?

Yes - as long as the Condo Documents allow such action which is usually the case.

Yes.  Your association should hire an attorney to prepare and file the lien documents for you.  The legal fees are an entirely appropriate expense for the association, and it may be possible to add a share of the fees to each lien, if the bylaws (as most do) include adding the costs of collection to unpaid balances.

It's important to do it as soon as possible, especially in this economy.  A unit owner not paying his association dues and assessments is the one more likely than others, to be falling behind on his mortgage as well.  If you record the lien before a foreclosure is started against the unit, your lien takes precedence over the mortgage -- otherwise, if you place the lien and notify the sheriff before the sale, you have to hope for some of the proceeds to be left after the mortgage and foreclosure costs (and any unpaid taxes) are covered.  If the foreclosure sale doesn't cover those back fees, they're gone.