Chongette,
Here's some info regarding starting business in Los Angeles, CA. There might be something I'm missing but I think it's a good starting point.
1. Decide what would be the legal form of your business - Sole Proprietorship, C-Corporation, S-Corporation, LLC, Partnership, etc. I suggest you form a Limited Liability Company because you will have a limited liability and will avoid double taxation. The problem is that you have to pay limited liability tax of $800 per year. I have a Sole Proprietorship because I can't afford to pay the tax. Check out the different entities:
http://www.sos.ca.gov/business/
2. Select your company's name. To see if the name is available go to
http://www.lavote.net/clerk/FBN_Search.cfm
3. Download the Fictitious Business Name Statement (DBA - doing Business As) from here:
http://www.lavote.net/Clerk/Business_Name.cfm . You can either fill it out in person or mail it to the address provided. The fee is $23.
4. Once you receive the registration, you must publish the FBN statement in a newspaper. Here's a list of approved newspapers:
http://www.lavote.net/Clerk/Newspaper_Circulation.cfm It costs between $30 and $150 to have it published. Most newspapers offer to fill out the FBN for you and then publish it in their newspaper but this only jacks up the price. File the FBN yourself and save money.
5. As soon as you get your Social Security Number go to
http://www.irs.gov/businesses/small/article/0,,id=98350,00.html and apply for an EIN - Employer Identification Number. You'll get it instantly.
6. For this type of business you will certainly need a special business license. This is where you can find more info:
http://www.calgold.ca.gov/ Type "food manufacture" (I tried "pastry" and "bakery" but nothing came out), click "continue" and then select your county and city for the complete list of licenses you will need. You can also click on "All Business Types" and select from a list of businesses.
I found out the following:
http://www.calgold.ca.gov/Results1.asp?TYPE=2099&CNTY=19&CITY=225
It looks like you will need many licenses and permits to do this kind of business. The most important are the Public Health Operating License and Business License, but you will need all listed there.
7. Once you have the Social Security Number, EIN, and FBN registration you can go ahead and apply for a Seller's Permit at
http://www.boe.ca.gov/info/reg.htm . Scroll down and download BOE 400 SPA. Any business engaged in selling and re-selling in LA (maybe throughout the state) is required to obtain Seller's Permit. You need to charge 9.25% in sales tax on every cupcake you sell. (This is the new sales tax in LA. It's different in different cities in CA)
Apply for your Reseller's Permit 30 days prior to starting selling your product. I made the mistake to get it right after getting my FBN registration. It's a mistake because if my business doesn't generate any income for 6 months, the reseller's permit will be revoked. Not a big deal because you can always get a new permit, but keep it in mind.
I strongly suggest you speak with a lawyer regarding setting up food manufacturing at home. It may not be even legal to do this in LA... I don't know. I will also recommend you get a job at a bakery and spend a few months working there prior to start your own business. Even if you're the best cupcake maker in Australia, you may find things here a bit different. The more experience you have the better the chances of survival of your company.
One more thing. It's very important that some time down the line you set up a website for your company. Ideally, your domain name should be identical to the name of your company. Go to
http://www.networksolutions.com/ to register a domain name. This is the only authorized website that sells domain names. You will find thousand of other websites that go through Network Solutions to register domain names and they charge a lot, sometimes double (that's how they make their money). I've registered my domain name the same day I registered my business name. I had to reject a few names for my business because the domain names were not available.
Here are some useful links:
http://www.irs.gov/businesses/small/index.html
http://www.sos.ca.gov/business/resources.htm
Hope this was helpful. Best of luck!
sasha