So I have this new Specialized hybrid bike since this spring and finally got caught in the rain last night.

Thought the bike would "blowdry" on the 10 mile ride home, so I didn't wipe it off.

Tonite on my ride I put air in the tires, but the bike felt a little sluggish.

Do I need to oil the chain or do anything else after getting the bike wet?

My owner's manual consists of a disk with 210 different owner's manual on it.

I hope books and papers don't go completely out of existence in my life time!

Thanks in advance.

Yes you should oil the chain. Also, check the air pressure every day or two. I know folks who clean their bikes after every ride, rain or not; but their bikes aren't any faster for the extra attention.

Mine is.
But seriously, most of your bikes problems will be lubrication related. A drop of oil can go a long way. Give it a wipe down once in a while, you'll see where dirt will build up, usually because of an excess of grease or oil makes the dirt stick. The brake pivots, derailer pivots, and chain all benifit from a drop of oil now and then. You'll notice a brake problem when the pads don't retract from the rim when you release the lever. When it happens you'll know. A drop of oil will free it up(usually).
As for the chain, when shfting gets sloppy, or the drive chain makes more noise than you think it should, it's time to clean and lubricate. What to use for chain lube can start wars, so you'll have to do your own research. After a rain ride, of on a dusty MUP, is a good time to lube the chain. Wipe it with a rag first, apply lube, and wipe off the excess. Takes a few minutes, you'll notice a difference.

Be careful of the type of "oil" you use. When you think oil you might be grabbing the oil can with SAE 30 in it........Most folks tend to use a lubricant designed for bikes.......but this will probably prompt folks to list their "home brews" or non bike related lubricants........

If you just got the bike this Spring this could be a combination of the rainy ride and the normal breaking in of your bike. If lubing the components does not correct the problem. Take it to your LBS and have them check the gears and brakes. As they wear they will need some adjustments.

Nothing wrong with asking these questions here, as you will get plenty of advice, most of it good, but that should not substitute for taking the bike to the LBS and getting their take on what your bike needs. It could be an adjustment issue or a lubrication issue or maybe something else that they could spot. They should be happy to give you some pointers on the kinds of maintenance you can do and what you might need help with. The shop I use offers free adjustments for a year on new bikes they sell. Different shops have different policies, but any shop should help you keep your bike working right and avoid letting problems develop.

Shhhhhh, dont tell anybody about my secret brew....Marvel's Mystery Oil (for my vintage roadies of course)

Be sure your brake pads aren't rubbing on the rim. You can check both wheels easily by lifting one at a time and spinning while you watch along the brake pads on both sides.

The chain and the rear casette get dirty from riding in the rain. Try cleaning your chain and then lubing it and check the rear casette. If it's dirty, take a rag and slide it between the cogs to get the gunk out.

I've adopted one tip from a tour mechanic: get a cheap paintbrush (1" or so), trim the bristles down some so they are stiff, and use it (and your favorite degreaser - I use Simple Green) to clean sprockets, deraileurs, and even the chain.

For the very basics consider Jim Langley's site:

https://www.jimlangley.net/wrench/basicbikecare.html

There are lots of other sites with much more information, but this is the stuff that will get you started.

I have a regular maintenance program- that I keep to if I remember it.

Used to be after every ride but now about every 100 miles and I check the chain for cleanliness- If the cassette is showing grease then clean the chain- clean the jockey wheels and Check the deraillers are in line, Same time check for cable fraying and line up of brakes. Little bit of lube on the Pivot points on the brakes and the inner cables get detensioned and oiled. I use Dry chain lube for this. This includes the brifter pivot points aswell. Chain is lubed on virtually every ride.

When the bike is dirty (May be every ride) then it is cleaned and all bolts etc. are checked for tightness.

Every 3 months then all the above and headset checked for tightness and any noise. I use Sealed bearings so not many problems on grit ingress. Wheels and check for true by spinning in the frame and checking against a brake block. Wheel bearings checked for any looseness by straining them by pulling on the rim. Chain is measured for wear and Cassette and chainrings checked visually for wear. Saddle and bar position checked just in case they have moved.

Then once a year the whole frame is stripped- parts checked and cleaned and re-assembled with new parts where necessary.

But most maintenance checks are done on a ride. That RD that has decided not to change smoothly- The saddle that has become uncomfortable- the noise that has suddenly appeared on braking----Any thing out of the usual and once I get home I check out why. Perhaps that is why I don't have to stick to the maintenance program as those tiny little faults are the start of a bigger problem that would only get worse on the next ride if not sorted ASAP.

The most important maintenance lies in riding, riding, riding to keep the motor humming.