What can i use instead of wine

If £ is the issue, lidl etc do very cheap wine that would do the job.

Otherwise maybe gravy or stock? Extra tomato sauce? Or even just water if it's a dish that already has plenty of flavours?

Hi,
if you want to avoid the alcohol and need a liquid use vegetable broth or vegetable cooking water. If you need it acid add a little lemon juice.

I thought I'd point out that when you cook with wine, the alcohol is burned off leaving merely flavour. In general, its best not to cook with wine that you wouldn't drink - it'll just give the food an unpleasant flavour. The same goes with using vinegar instead of wine - an absolute no-no unless you're making saurkraut! You can try to introduce flavour by cooking things down until they're thicker on a slow to medium heat. This will give you a richer thicker tomato sauce, for example. You could also try adding stock cubes. I use vegetable bullion, which is like a stock cube, but liquid. A teaspoon of this in the cooking adds a great deal of flavour!