OK. That's all interesting stuff. Here's how it works in the UK:

VAT (sales tax)

VAT is analogous to Sales Tax, except that it all goes to Central Government. This is generally 17.5%, but is less for some things (e.g. household fuels) where it's 5%. Some items (those classified as essentials) are not subject to VAT.

VAT is included (where applicable) in the price tag shown on each item in the shop, so there's no need to remember to add it on when shopping. I always get caught out by this in the US.

The exception to this rule is office supplies, computers, etc.. These are generally bought by businesses that can claim the VAT back, as long as they charge VAT on their products/services. Here the price is generally listed both with and without VAT included. Businesses still have to pay the VAT, but because they can claim it back, the lower price is useful to them.

Duty

Certain other things (petrol, diesel, alcohol, cigarettes, etc.) also have "duty" added to the price. This is partly a way for the government to chisel more money out of us, and partly to discourage us from smoking/drinking/etc..

Income Tax

Income Tax is normally paid monthly. Each person is assigned a "tax code", which tells the employer how much pay to withhold. This money is sent to Central Government, via the Inland Revenue (the taxman). If you're self-employed, I think that you have to do this yourself.

At the end of the tax year, you generally have to fill in a tax return, which tells the government what else you earned that year (interest on savings/share dividends/etc.). Then you'll send that in for assessment, and the taxman will either send you a bill for the outstanding amount or a cheque for what you overpaid. Alternatively, the taxman has the option of adjusting your tax code so that you pay more/less next year.

Often, you won't have to fill in a tax return -- your employer will send a form P60 to the taxman at the end of the year, and they'll sort it out from there.

We don't have to fill in any form similar to your I-9. The taxman generally assumes that you'll earn the same this year as last year, and assigns you a tax code based on that. If you've never worked before, you'll get assigned a special code and have to pay "emergency tax". Any discrepancy between this and what you should have paid is sorted out at the end of the year.

Income tax is assessed on an individual basis, not per household.

National Insurance

Then there's National Insurance, which is in addition to Income Tax. There are two flavours of NI. Employee NI is withheld from your monthly salary. Employer's NI is paid in addition to this, and doesn't come out of your salary. Obviously, the employer will factor this in when he decides whether to hire someone. This goes towards the NHS and State Pension scheme.

Council Tax

We also have to pay Council Tax, which goes directly to the local authority, and is assessed according to the value of where you live (whether you own or rent). The local council can also apply to Central Government for extra money from the Exchequer.

Then there's all the other little taxes, like the Road Fund License and stuff like that.