This will probably be one of the hardest tasks you have associated with getting your product to market. Many packaging manufacturers simply don't handle small quantities so it's important to find a supplier that works with minimum quantity or small quantity orders at the very beginning. Fortunately there are now many resources available to someone starting the process of packaging their product.
First you need to decide the absolute minimum quantity you can order. Chances are you may end up ordering more but what you don't want is a lot of excess packaging that you paid for and can't use or packaging that ends up not being what you were expecting. Your packaging will evolve too so don't be concerned if you can get exactly what you want the first time.
Start by asking your existing resources or vendors who they know and who they use or recommend as a packaging supplier. Believe it or not sometimes you can find the name of the packaging manufacture on existing packaging too. See what you like then try to find out who made it and give them a call.
Keep it simple to begin with. I know you have visualized fantastic or exotic package designs and as your business grows you will be able to order custom packaging for your products. But in the beginning you may need to decide to keep it relatively simple and use what is readily available
Today there are many great options available in small quantities. Suppliers have finally recognized that there are many small business clients out there too. Before you spend a lot of time and development creating a package you can't afford or can make you need to determine what's available at the right price and in the right quantities. I know your product is fantastic, but you still may need to start out on a smaller scale than you envision.
Here are places to look for suppliers of small quantities.
Yellow Pages:
Pick up your local yellow pages. There are a lot of companies known as packaging distributors. They buy in large quantities and the break it down into smaller units for resale. Many of them have distribution centers around the country. Look under container, boxes, shipping materials or supplies in category headings.
Catalogs:
There are numerous companies that have catalogs of packaging supplies and materials. Many of whom carry a large variety of stock sizes, ship to your door and have no minimum order quantities. Uline is a good example of this type service of carrying a variety of packaging products and supplies with delivery in a few days.
Trade Associations:
Contact the association headquarters for the type of packaging you seek. They help their member get business so they will know which of their members deal in small quantities. Many times there are member directories right on the website.
The National Association of Container Distributors is a good example. NACD is a professional association of rigid packaging distributors who supply bottles, tubes, pumps, sprayers and other closure systems and most of their members deal in small order quantities.
Internet:
With the advent of the Internet you don't need a storefront presence. Many of the companies broker packaging materials, they source supplies and do all the work for you. They make carry packaging in conjunction with other products especially in the niche markets.
One of my favorite sources for packaging innovation around the globe is WebPackaging
http://www.webpackaging.com/. They are the largest global online packaging resource It just so happens that I write articles on packaging for them too.
Niche Markets:
There are many niche market associations out there for example if you deal in the hand made toiletries and beauty industry there is an association dedicated just for them. Indie Beauty http://www.indiebeauty.com. There are numerous packaging supplier members that provide small quantities of packaging for this market.
Container Stores And Other Retail Outlets:
Just by their name you recognize that they are a source to find the most unique containers. Many people just go to these stores and buy supplies. Other stores include craft stores, hobby and home centers where they have lost of decorative containers and accessories.
Lastly don't overlook current suppliers. They have existing relationship lean on them to help you find appropriate resources. Designers, graphic artists, product producers all have sources. You may be able to open a door to a relationship even if your quantities aren't quite large enough.
Don't wait however till you have a product then end up in a bind to get a package made. This process should start at the very beginning.