Lighting a large area

Greetings, i have come across a large issue regarding my lighting , the TDN was a bit confusing. so i needed to clarify and ask for some assistance. I have a large square area, is there a way to create a selflit particle source. Essential im looking to create something similiar to the sgredlightdatablock, which only illuminates against a object. i want to create essentially a globe or globes of light that illuminate a large area, much like the campfires, which are illuminated but i dont want the other particles, just the ambient light. Kinda like flouresant lights but on a more large scale. and yes i have looked at the spotlight and go those working for the most part. but in this case i need a larger scale of light illumination. (cavernsize). I have looked at the other sites, but most are specifically laser, exposions and spotlights.