To address the original question as to where to get some plugs... we all come with a pair built in... I use my thumbs.
There is no need to soak a hose for hours on end to clean it. Simply fill the hose with some warm soapy water cover the ends with your thumbs and swish the water around for a while. Count to 30 if it makes you feel better. If your trying to kill germs try putting some mouth wash in your hose and doing the same thing. Once you pour out the suds/mouthwash you can turn your faucet on and press one end of the hose to the faucet and hold the other end in the sink so you dont flood your bathroom.

when the water runs clean IE: all rinsed you can hook the hose up to your machine and use it... shake out any excess water you may have in the hose first though.
Once again the big issue of to clean or not to clean varies from place to place. If I am sick with a infection I'll usually clean a bit. Hard coughing can contaminate the end of the hose near the mask... wether or not you could reinfect your self doesn't concern me as much as the gross factor of having air fly over left over cough film from what ever was bothering me before.
As to the higher risk of pneumonia, I've had that condition now 3 times and only since I started on CPAP. My suspicion is that gunk from my sinuses is getting aspirated into my lungs now and then because the CPAP at higher pressures appears to suppress my cough reflex a bit. So I accidently breath in the gunk from my sinuses, post nasil drip.... yada yada. This junk then makes my lungs mad and pneumonia follows shortly there after.
As for the cleaning regiment. It's for worse case... if you live somewhere where the humidity is high all the time and maybe you also have mold growing near by... you have to clean regularly or your going to get sick. Especially if you have a mold allergy. If on the other hand you live somewhere else. You may never have to clean.
I can say this based on real life experience as I've seen both outcomes. House I lived in before had a mold problem... I had to clean regularly or my hose and mask would start to look like a petri dish with black mildew growing everywhere it was disgusting. However where I live now I dont have that problem. Just clean my mask with a sent free baby wipe to keep the face oils down.
You need to start off and clean how you feel comfortable. After a while if you feel adventurous go a while with out cleaning and then examine your hose and equipment closely. If you dont see any signs of any thing in there that shouldn't be you can probably cut down on the cleaning or not clean at all and just replace the parts once a year or as they wear out.
All I can say is for the most part try to use common sense try not to be gross, at least keep the mask clean where it touches your skin... etc.
Either way. Cleaning or not cleaning can become a heated topic, and dont bring up the "S" word.
Oops never mind. The S word has been spoken. Runs to the kitchen for a fresh bag of microwave popcorn.
Carry on!
Rest well,
Gryphon