Check the concrete walk around the pool for sagging. This might provide a clue to the location of the leak. I would suspect the skimmer. Grab an old bottle of the red stuff from a test kit and (with the water still - pump off) slowly release a drop or two around the edges of the suspected leak - the red indicator will quickly show the area to be patched. I used epoxy putty. (Remove the bottle from the water before releasing it so the pool water doesn't dilute the pH indicator solution.
Re-grouting is easy. Get a box of grout, lower the water level in the pool, and start smearing it around. When dry, a damp cloth removes the excess from the tile.
I'm in Detroit (freezing weather) and the 30K gal pool hasn't needed to be resurfaced in 20 years.