You'll also want gloves. I ride with half-finger leather gloves that I replace every year (as I usually wear holes through the palms). I don't buy biking gloves - I go with weight lifting gloves. I find they're more durable, although not as light or breathable. I don't just bike, though - I do weight lifting and lawn cutting. Doing all three at the same time really ruins your hands.
If you're doing more extreme riding, you may want to consider gloves with full finger protection and knuckle guards.
Always wear a helmet. If you're doing extreme riding, you may want a full-faced helmet.
Hydration pack.
I wouldn't go for a saddle bag - camelbak should do everything you want.
You can get a multi-tool - it'll help you in the case of break downs.
Spare inner tube.
Inner tube patch kit.
As for lubes, DON'T use WD-40 on any part of the bike. You can get proper lubes at the lbs. You can use automotive grease on the chain, if you want.
I strongly advise wearing sunglasses, or some other form of eyewear. You'll be thankful when that insect dings off the lens and not your eye. Stops the branches from tearing up a part of your face too.