First off, you will need products to sell. Be very carefull when looking for dropshipping suppliers online there are many unscrupulous people that will take advantage of you. There are a couple of rules to follow when choosing a dropshipper. One, a real dropshipper will never charge you a fee to sell their products. Two, a real dropshipper will want proof that you are a legitamate business. They may ask for any or all of these; Business License, DBA, Federal ID (EIN), and/or Sellers Permit. A very good source of real wholesalers is the WorldWide Brands OneSource Directory. They sell a directory of REAL dropshippers and light bulk wholesalers that they have resarched for you.
Secondly, you will need a venu where you can reach prospective customers. You may want your own website or to sell your products on ebay. For your own website you will need a domain, a webhosting account, and shopping cart software. EZ Dropship Cart is a great cart for dropshippers. Ebay is also a great way to reach perspective customers, the only problem you may run into is that some manufacturers place no auction restrictions on their products.
Thirdly, you will need a way to accept your customers payments. Paypal is a fast easy way to get started, you pay fees only when you have transactions. While credit card processors offer lower per transaction fees, they require setup fees and monthly fees that are geared tword large voulme sales.
Lastly, you will have to get Legal, this is where most people faulter. They think it sounds hard, complicated, and expensive. And actually it isn't any of those. Just visit your states website to find out what you need to do business. In most cases a DBA can be used in place of a Business License. But either way most states charge around $20.00. Some states, not all, require you to get a Sellers Permit or Resale Certificate. Either way all the resources you need should be available at you states home website, usually under a small business section. While you may not have any employees I highly recommend getting a fedeeral id. It costs $4.99 online and you get it instantly.