I recently built up a fixed gear bike from an old repainted steel frame. Its always been a problem but it is now becoming more and more annoying. Anyway, the problem is one of my rear fork ends/dropouts is not the same shape or angle as the other; this causes my rear wheel to be out of true almost all the time which causes huge problems with the chain because the tighter the axle bolts get, the further left the wheel goes. As you can see, the hub doesnt sit flat on one side. Any suggestions how to fix this?

That is not out of true. Wheel is fine, but it is sitting cocked in the dropouts. You need to have a good bike shop align them for you or a frame builder if there is one near you. If the frame has little value, you could try to do it yourself with a vise or vise-grip pliers.

A photo would certainly help, but offhand I suspect that the dropouts aren't parallel to each other. Special tools are used to correct this, but there is some DIY. Without the chain on, bolt the wheel to one side only. And note where it ends up on the other side. Nowbolt it to that dropout only and see if the first side goes back to where it started.

If dropouts are parallel, either side tight will have the other in the same place.

The other possibility is what I see all too often on fixed and speed bikes is that people over tension the chain. Any tension is overtension and will pull the wheel forward or even buckle a dropout. The chain must be slack a all times with about 1/2" free vertical play in the center of the lower chord.

Need more help, post afewphotos showing the specific issue.

Another couple of possibilities are that the faces of the drop outs are getting gauged, the axle's nuts have dug into the dropouts' surfaces and as the nuts are tightened they tend to settle into the gauges. And/or the dropout slots are not parallel slots but that they have opened up and have a "V" shape. Again as the axle nuts are tightened the axle slides/rotates about and seeks a different position then intended.

But without photos it's impossible to say for sure.

There is a way to tighten a nutted axle so it tends to stay in place, many people don't know of this "trick". Start by tightening one side's nut a bit. only enough to contact lightly squeeze the dropout. Then go to the other side and repeat. Go back to the first side and slightly tighten a bit more, repeat with the other side. if at any time you notice the axle rotating (and then that side's nut will no longer be tightening up) you've gone to far in that side's tightening. So only tighten the nut to just less then when the axle rotates within the drop out slots. After a few back and forths the nuts should be pretty tight. And without any axle rotation the axle hasn't had much tendency to drift along the slot's length as well as the bearing lock nuts haven't had the chance to change their position on the axle (and if they did the bearing adjustment gets affected). Now that the axle is well tightened in the drop outs we can go back and address the exact location within the dropout slots if needed to adjust the chain tension (if not already correct). By fully loosening one side and pulling the rim at it's passing through the chainstays you can move the axle back or forward in the slot. Then fully retightening will trap the wheel in it's now cocked position. Note since the other side's nut was not loosened it acted as a vice, keeping the axle from rotating. Now go to this second side nut and loosen, pull the rim to be centered between the stays and retighten the nut. If you do this well the wheel is now centered, the chain is properly tensioned (which for a non spring tensionered drivetrain is NO TENSION) and the axle has not rotated (which as said caused all kinds of issues). Andy.