Most places that are still doing PCR testing require you to fill in your info before booking/seeing appointment times, but there is generally a lot of availability because there is a low demand for tests.

Places like Walgreens/Rite Aid/Quest/Labcorp are now offering at-home PCR tests that you just pick up and drop off.

This place offers same day PCR and you can see appointments without having to fill out a form.

You can also order at-home molecular tests (PCR-like) from Lucira and Cue.

Dems removed all the Covid funding from the latest government spending bill, despite requests from Biden to leave it in. Unless something else is done to provide additional Covid funds, vaccines, treatments (Paxlovid, etc), and testing that are currently free will go completely to the commercial market at some point in 2023 and everyone (or their insurance) will have to pay out of pocket. That will make it even harder to find or afford a PCR test.