Basically just a collection of links to either 15mm manufacturers that I've used and want to help promote, or online stores that sell 15mm figures or modelling resources that work well with them, or just random sites that have good information and/or pictures of 15mm stuff.
Of course, I'm always open to suggestions of more places to spend money at...
Copplestone Castings - Check out the 15mm Fantasy range for some excellent Hairy Northmen (and some clean shaven ones too) as well as Snow Trolls and Conan style Barbarians. Also a small selection of resin scenery. The sculpts are absolutely amazing, can't recommend them enough.
Fighting 15's - A selection of AB Figures historicals, Camelot historicals, Eureka 15mm and 18mm stuff, Oddzial Osmy historical and sci-fi. I especially like the Eureka 18mm Man-orcs, which make excellent Uruk-hai for a lord of the Rings force.
Flames of War- The official Battlefront site.
Plastic Soldier Company - Some excellent WWII kits, infinitely easier and less frustrating than the official resin/metal hybrids. Makes putting together a Flames of War force a fraction of the price, especially when you add some Warbases (see below) mdf bases. Love my German Armour (Panzer VI H's and Panthers) for the ease of assembly and conversion possibilities.
Ral Partha Europe - RPE is now the manufacturer of the long discontinued Demonworld line from Hobby Products. Exceptional quality miniatures, and excellent customer service from Paul. Despite their age, these are still some of the best 15mm models around. The small packs are great for picking up tasters or a small skirmish force, or a Mighty Armies force, and the larger packs are great for mass battle rules. There is also a tasty selection of Resin Scenery that works well with 15mm models.
Splintered Light Miniatures - A huge selection of 15mm fantasy and historical miniatures, plus the 18mm Splintered Lands lines. No matter what you are after, from Armoured Badgers to Zombie Horses, David is bound to have something to suit your needs. Again, excellent customer service from a genuine guy, and a cracking wee range of resin terrain pieces to boot. Pumpkin Houses included!
Tin Soldier UK
Antenocitis Workshop - A superb selection of modelling materials and basing stuff. A one-stop shop for all sorts of cool stuff to really kick your bases up a notch or two.
Renedra - A good source of plastic bases.
Veni Vidi Vici Transfers - A good selection of transfers for 10-15mm models, available in a range of colours.
Warbases - High quality laser cut MDF bases from Martin. Highly recommended due to him being a local business and all-around great guy. Very accommodating with custom orders, and does a cracking range of 15mm 'flat-pack' buildings. Really impressive stuff.