I'd start with a book on sail trim, or calling a local loft and asking when you could stop by to talk to someone. (And if they offer to come visit your boat, by all means say yes!)
If your sails are 11 years old, I would expect that unless they were stored indoors for ten years, they're shot. When you lay hands on them, are they nice and smooth? Feel like commerical bed sheets? Smoother? Or do they have a shiny plastic coating still on them?
Usually by the time the plastic coating is gone, they have lost shape. Shortly after that, they will be blown out, usually around the same time they feel like you could use them if for bed sheets if you really had to.
But blown out sails alone may not be the problem. Assuming you have the original rudder on the boat (sometimes they get replaced incorrectly) and assuming the bottom is reasonably clean (not hauling around mussel farms), every boat still has a center of effort, a pivot point roughly around the center of the boat. The boat acts like a windvane. Apply pressure behind the pivot point, and it turns one way. Apply pressure in front of the pivot point, and it turns the other way.
If you have too much sail area on the wrong side of the pivot point, you will always be turning away from the wind, or at least, not pointing well into it.
This can come from having the wrong rake (tilt angle) on the mast. That can come from the rigging (forestay/backstay) not being tensioned or sized correctly. Or having the mast located in the wrong position, if there's no fixed plate to secure the bottom of it. Or, having the wrong sails (too much, too little, too blown out) as well as having the sheets led to the wrong position.
If that sounds awfully vague and complicated...yeah, it can be. There are a dozen "little things" that are not real obvious, that make a difference in pointing ability. Even the length of the spreaders matters. Longer spreaders may make a stronger rig--but they prevent the genoa from being trimmed in tight. Could even be the spreaders were replaced on your boat, or, never actually the right size for the rig design. (There's some variation and tolerance in builders sometimes.)
So really...getting someone from the loft out on your boat might be the fastest way to go over this all. That's easier now in the slack season, and with 11 year old sails...I think you'll be AMAZED at how much better the boat does with new ones. The extra teaching that the loft can do, is often worth the extra cost of dealing locally.
Otherwise, ask around, maybe your dockmaster or someone at your local chandlery can connect you to someone more experienced locally, who'll gladly come out and take a look for the price of lunch or a couple of hours on the water.