How difficult is it to replace the drive axles on a Honda Accord by yourself? Should I also replace the oil seal at the same time? Somewhat mechanical, but never tackled something this big.

well, if the seal leaks , it can be many reasons.
1: bad seal.
2: damage to seal bore hole done by not using proper tool and scraping the bore. (#1 , install fail)
3: cheap flebay no name parts ? or seals. (junk is junk)
4: shaft is damaged,
5: bearing worn allowing (bouncing) seal to get beat to death.

good seals fail for #5 reason, top reasons, all machines.

it does happen commonly that New parts are defective,see if the alignment shop can confirm to parts that the axle was defective or milled improperly

You will need to remove the right side axle and change that differential seal, to stop the leak.

hi this sounds like the oil seal that is in the gearbox/transmission is worn, which is oddly called drive shaft transmission oil seal..there is no special name for it, unless you have the correct tools for the job this can be a bit of a long job, mostly disconnecting the ball joints from the hub there are special tools to do that, but once you have the drive shaft out, its a simple case of pulling the old one out and tapping in the new one, make sure you have a bucket or something to catch the oil in when the drive shaft comes out, it makes allot of mess..its probably about a 2 to 3 hour job for an armature to do with the right tools...the seal is probably about 10 to 15 bucks may be cheaper...hope this helps

First have to determine where are you loosing it from.
Possible engine oil leak areas : Valve cover gasket,oil pan gasket, rear main,oil filter. crank or cam shaft seal, oil pump. Pcv valve.
If its transmission oil leaking here are a few areas of interest: shell of transmission( depending where on the shell could be oil pump, or converter., vents, and axle seals.
If your not capable to jack the vehicle up and look for the leak , then take it to a repair shop.
Keep me posted

It depends on the engine. The 4 cylinder engine uses a timing chain, and is generally replaced every 150,000 miles (Honda doesn't give a specific interval) with the water pump (driven off of the timing chain) and timing gears. On the V6 engine, you have a regular rubber/steel belt, and it is supposed to be replaced every 105,000 miles, according to Honda. The water pump is driven off the belt as well, and should be inspected or replaced. (I recommend replacing the water pump anyway, just to save yourself any future trouble)

check you valeve cover seal it could be leaking and the oil running down in that area

Not that difficult, raise and support the rear of the truck and remove the wheels. Might as well replace both sides so you know you have new seals, remove the differential cover and drain the fluid. Once differential is opened and cleaned , remove the axle "C" clip that hold the axle in place and slide the axle out. Once the axle is out remove the wheel seal and clean around the area. This would be a good time to replace the wheel bearing too since you have access to them and there not that expensive. Install the new bearing and seal, note make sure you oiled the bearing and seal before installing it back and take care when installing the axle back in and "C: clip. Use RTV silicon gasket maker to seal the differential cover and wheels back on and lower. If your lazy like i am, you can drain the differential fluid and replace it with a 50/50 mix with gear oil and Lucas engine oil additives. That may stop the leak and get you a few more miles. You gear oil is 75W-90 and the capacity is 2.6 liters and 3.6 liters if you have the 11.50 Ring gear. Good luck and hope this helps. 

Take valve cover gasket bolt out replace... An when you do the lower crank seal you have to take off oil pan.. Big job but it can be done..

No, you don't have to pull the engine. Many of those problems are fixed by removing the wheel, and the plastic inner fender. It's probably a crank seal, or a power steering hose. PS- You mean the passenger side... don't you?