Another advantage to using towers for duplication is that they offer (as a menu item) a compare mode that will verify each DVD to the master and will reject a disc as bad if a single bit is found to differ from the original. It does take an extra 20-40 minutes to run, but it saves watching dozens of DVD to check for quality and ensures your client of a good DVD, as long as your master is without fault.
For labeling, I don't recommend stick-on labels, but rather the coated DVDs that are ready for direct printing. They are readily available, even in your local office supply store. Be careful, though, as there are different types. Some are inkjet only, others thermal only, and you have your choice of a silver or white surface in both variety. There is a third type, Light Scribe, that are designed for with a specially equipped recorder that's capable of etching a label directly onto the non-write side of a disc. But because of the expense of the media and length of time to actually create an image, the fact that LightScribe towers are only just coming out, and the fact that these drives can't create full-color, photo-like images like inkjet printers, these aren't viable options for many videographers today.
To save time and create a "branding" for the DVD, I like to use a scanned image of the event's program for the DVD label or have the show's sponsor provide an image or photo. There are also programs like PixelPops' Pixel Mixer that require little or no artistic talent to create professional-looking labels. Once you have created the image (in Photoshop or other standalone program), you need a disc-compatible labeling program to center the image on the DVD, blank out the center hub, etc. Most CD/DVD printers come with this type of software. Not only can these programs take care of the printing, they are also great at creating the actual label. I use Discus Labeler software from Magic Mouse, which came with my Epson printer (an ordinary photo printer that also prints on surface-printable DVDs). The upgrade package ($30) gives you tons of stock backgrounds and uses the font base that already resides on your computer. It also allows you to import labels from other programs and supports all types of labels (even VHS) and printers. It's a surprisingly good program for the money.
To actually place the image on the DVD you need a printer and if you are not doing 1,000 discs a month, you can use a "one off" printers like the Epson R200 or R300, which start at under $100. Larger orders require a robotic printer. Here, standalone machines like the Microboards PrintFactory or the Primera Bravo (they make a printer-only unit) are the front runners. These start at $1,200 (street). Again, some of the combo units (duplication and printing) may be the perfect entry-level solution for most people starting in this area of the industry.
The last step before distribution or delivery is the packaging. After the time and effort you've spent designing the label for your DVDs, why cover it up in an Amaray case or with an over wrap, and spend money and time to do so? What works for me is the poly-vinyl jewel-style cases. They are clear and nearly indestructible, with most having a hub lock that keeps the DVD in place when the case is opened, and the 5mm thickness takes up almost no space. In quantity, these are available about for 15 cents each. Using the poly cases will also lower your mailing costs. You can use the smaller CD/DVD-size bubble-pack envelopes (size 0). If buy the mailers in bulk, you'll pay half of what they cost in the local office supply store. Total shipping weight for a single DVD is less than 3 ounces, which sets the current mailing cost at 83 cents for USPS First Class Mail.
If you are mailing in quantity, look into one of the third-party, online stamp companies. Monthly fees are $10-15 a month, but the convenience justifies the cost. Most of these allow bulk mailing using a database or spreadsheet which will allows you to print labels with postage for hundreds of packages (all of the same weight and postage type) in one shot, automatically. The two major companies are Stamps.com and Endicia Internet Postage (I use Endicia). Both offer similar services but have slightly different offerings, so read their contracts and list of services before you choose one. You will have to get an accurate scale to determine postage amounts, but they are available via the Web for $10-25. These services are adding new products often and even offer insurance (at a rate cheaper than the post office). If you do mail or ship your product, be sure to calculate the entire cost of shipping (packaging, postage, shipping labels, stamp contracts, and even your time packaging and your trips to the post office.