I have a 2001 Honda Civic with a 1.7 engine. The number 1 and 2 cylinders have some oil in them so I know I need to replace the tube seals. I've never done it before. Anyone have any information that you'd mind sharing on how to do it? If anyone has any pictures that would be great! Thanks

 

Get a valve cover gasket kit. It should have the seals in it. I got mine from HandaPartsNow but have also bought the kit from carquest. Remove, the wiring harness, cover, unbolt the retainer for the throttle cable, and unbolt the valve cover. Wiggle that joker off of there and cuss at it a little (I think this helps.)
Inside the valve cover you will see what appear to be rubber rings. They are actually plastic coated metal rings. Pry them out with a big screw driver. Replacements should be in your valve cover kit. Peal the old valve cover gasket out. I like to spray any gasket, ruber or otherwise with "candy tack" or copper spray-a-gasket to keep them from scooting around. Put the the plug tube seals, rings, and gasket in the valve cover and CAREFULLY replace. Those tube seals like to snag on the tubes and if they get wrinkled, they leak.
Also get a camshaft cover (on the passenger side of the valve cover.) Its just a black piece of plastic with a slot in the middle, that snaps in and can be popped out with a screw driver. The factory ones leak all the time. When you install the new one put a bead of silicone around the edge to seal it and hold it in place.
GOOD LUCK. Let us know how it turns out.