Looking for a job: Bar work

Depends on so, so many things.  A lot of the hotels / bars / Chiringuitos have shut for the season so there is a surfeit of experienced staff looking for positions.

How's your Spanish? even in an English-themed bar or migrant hangout, you are still going to get Spanish speaking customers.

I won't even bother asking about passport / visa etc because I'm sure you'd not be asking if you weren't legal to work here

No. Loads of bars closing over winter, many of those open are reducing staff numbers and staff retention lies with the locals.