Hi hockeyfan,
While I don’t follow hockey a lot during the regular season, I follow it enough in the playoffs to know that today is not a good day for the Canucks which are “my team” 
On to mattresses though …
There is one factory direct manufacturer I know of right in Indianapolis …
http://www.sleepbacktherapy.com/index.php (Niagara Therapy) Indianapolis, Fort Wayne, IN. They have latex and latex hybrid mattresses (with innersprings or polyfoam) as well as memory foam mattresses that you can choose your own components and design your own mattress. Knowldgeable about mattress materials and they use good quality materials in all of their lineup. Well worth a visit for those that are in reasonable driving distance.
There are also several other factory direct options in the general area. Three of them are run by separate parts of the same family of which one is very close and the other two are a little further away but still within reasonable driving distance in your general area (they are not connected to each other) along with a regional factory direct manufacturer and a local mom and pop supplier that sells high quality latex mattress components as well. They are …
http://www.holdermattress.com/ Kokomo, Carmel
http://www.holderbeddinglafayette.com/ or http://www.fixr.com/sp.holder-bedding-inc.html if their site isn’t working. Lafayette
http://www.holderbedding.net/ Anderson, Muncie
Furniture Row® Store Locations - Store Hours & Addresses Lafayette, Terre Haute.
www.diynaturalbedding.com/ A local mom and pop supplier in Lafayette that supplies mattress components including 5 different firmness levels of 3" Dunlop layers, wool batting, and mattress covers (including wool quilted) that you can put together at home. The work from their home where you can go to test different layer combinations. Since these are components only, you can build a mattress without a fire barrier. As you can see from their many forum posts and contributions (see here), they are knowledgeable, experienced, and helpful.
While all of the Holders may be better value than many larger brands … I would definitely include the one in Lafayette in your research. More about the different Holders is in this thread.
There is also a factory direct manufacturer based in Jeffersonville called Bowles Mattress which makes their own line of mattresses and also manufacture Lady Americana which would also have better quality and value than most of the mainstream choices you are likely to find locally. They have several independently owned factory showrooms in the Indianapolis area including Longs in Indianapolis and Walls Mattress nearby (they have a retail locator here).
Some wholesale manufacturers that supply some of the local retailers that may also have retailers near you include …
Jamison also makes some high quality mattresses which have better than average value and they also have a retail outlet finder on their site (although the closest one is still a fair drive away).
Pure Latex Bliss also makes a line of very high quality latex mattress if you are looking in that direction and also has a retail outlet finder on their site.
The closest PLB dealer to Indianapolis is in Zionsville http://www.villagemattress.net/contact.html . One of the outlets that seems to carry them also carries Jamison http://www.thompson-furniture-columbus.com/index.html (although they don’t list the PLB on their site)
http://www.sleepdutchcraft.com/Locator.aspx is a wholesale manufacturer based in Celina Tennessee that also makes some better quality/value mattresses that would be worth including in your research and they also have a retail store finder on their site.
http://www.clarebedding.com/dealers.asp They are a wholesale manufacturer that makes Restonic but they also have a retail outlet finder and there may be a store near you where you can test them. Clare bedding makes “all latex” versions of Restonic (some regional Restonic manufacturers use polyfoam over the latex)
Southerland mattresses is an independent wholesale manufacturer based in Nashville, TN that are carried by some of the retailers in the area including http://indianamattresscompany.com/ and http://www.villagemattress.net/ that may also be worth considering.
http://marksmattress.com/ Retailer with stores in Crawfordsville, Lafayette, Richmond, Terre Haute, IN (and others that are farther away). Carries their own line of private label memory foam and latex mattresses called Sleep Natural that may include some better quality/value options that may be worth considering as well. I would avoid the major brand and liquidation mattresses that they also carry.
I would always make sure that any retailer or manufacturer you are dealing with will provide you with the information you need to make an informed choice about the quality and durability of all the materials in any mattress you are considering (see this article) so you could make sure there are no lower quality materials or weak links that can compromise the durability and useful life of a mattress and make more meaningful comparisons with other mattresses.
These are the better choices that are reasonably close to you that I know of.
Phoenix