As BB is a pet house rabbit forum, many of our members are not experienced in the care of baby bunnies, so I encourage you to do additional research. Here is a section from the BB rulebook that you may want to reference- 
 
D. Discussions of Breeding and Rabbits as Livestock: Discussions involving intentional breeding (of any animal) and meat & fur rabbits are not allowed.
• Accidental Litters: We are not a site or forum that has the necessary experience to advise you in this matter. It would be better for your bunnies to use reliable resources for pregnant/nursing does and their babies. Here is a list of resources that you may find very helpful:
•http://www.bio.miami.edu/hare/surpriselitter.html
•http://www.rabbit.org/care/babies.html
•http://www.rabbit.org/care/newborn.html
•http://www.mybunny.org/info/newborn.htm
-Rabbitsonline.net, caters to a broader range of experience, may also be of help.
-Be sure to seek vet care and advice.
-Do not use this forum to give or sell bunnies as well.
-Since we don’t allow prolonged discussions regarding this, the thread will be locked.
-We hope you will find the above resources useful. Please feel free to to ask about other aspects of caring for your bunny  
  
  
Unfortunately, you really do need to take the baby to the vet. Broken limbs are painful and will continue to be painful throughout the bunny’s life if not treated. You can ask your vet if you can work out a payment plan. Hoping all works out for your little one.

I’m very sorry the baby broke it’s leg. Baby animals heal remarkably well, however even if it heals in such a way that it doesn’t cause the baby pain, he/she will definitely be in pain now with a broken leg. Vet visit is a must for painkillers at the very least. Depending on the age on the bun you would probably be better taking it into care so that it can’t get stepped on or injured further, plus you will need to keep it confined to reduce movement for the leg to be able to heal. It may need to be wrapped as well to keep the bone in alignment, but that sort of thing is really under vet discretion depending on how an x-ray looks. Some can heal without wrapping providing they are put on pain killers and have their movement restricted. If you are not going to provide the poor bun with painkillers, you will at least need to make a final visit to the vet for the poor little bun.

To aide with healing, make sure you provide lucerne hay and pellets to the baby (if you’re not already) as the extra calcium will be beneficial to the healing process.

All buns are going to have to head to the vet so the little one can get its break checked. If you can tell its an obvious break, a vet is going to seriously have to look at it the sooner the better