I have seen here that some have quoted £12 per hour for domestic cleaning, I'm not sure if this included cleaning products but I do know some customers will supply everything you need. I also guess it depends on where you live. If you live in an area where there is 'money' than you may find you'd be in a position to obviously charge more for your service. Only you can be the judge of your local market.
As shelton has noted, it is important to work out your costing - no point in charging a set figure if that will not cover all the necessaries.
As for commercial cleaning - you really are getting into a different area with different rules apply from the start. I don't know any businesses that will charge by the hour, unless perhaps, its through supplying an additional service.
Commercial Cleaning generally is based on all sorts of things and too much to mention here. You can search here for commercial cleaning or the internet, I promise you will find loads of stuff that will give you the information you need regarding that area of cleaning.
The pricing of commercial premises can/will depend (but this is in no way an exhaustive list)on area, employees, products, machinery....please also remember, Health and Safety, Employment Law and insurance (which you'll still need for domestic....don't want to go breaking any valuables if you're not covered!).
I hope the above is of some additional help.