yeah, I was wondering the same as Tom, what if it just a stuck valve stem? Easy to replace, no tire hassles at all. Cheap enough, even with buying the small tool. Or having a good needle-nose.
If it IS the stem, I fully agree, you have to break the rim bead. U can decide how, some DIY advice given. They do work. Seating the stem against the rim will require the front bead to emrge from the rim, stems have two beads for the sealing properties.
Ucan get the tool cheaply, or I bet local tire shop might let ya use one real quick. If ya go through all the hassle to break bead yourself to replace a stem, ya really need to ensure the stem gets seated!!!!!!!!!!.
Generally, if not on-the-road repair, I'd take it a shop, let them bust the bead and install a new stem, in-out within 10 minutes, say $10 bill.