I agree with Karen.

Check if there is any feral cat rescue group in your area. If you will provide the funding, they will gladly help you trap the cat, and they have reduced rates with the vets they use, to have him checked over, and dewormed, deflea'd and so forth. Talk with them.

There are a few ways you can find a local feral cat rescue group:
1. call your spca, they may know who are in your area
2. Use Google, search: feral cat rescue Indiana
You can add your city at the end if you like!
3. Look on craigslist, and if you dare, even post and ask for the name of a local group. If you do post, do not use your regular email address, set up a second email just for that post and even then don't put it in the ad, use their anonymous reply feature.
4. Ally Cat Allies can direct you to a group in your area. Here is the link for their referral page: http://www.alleycat.org/page.aspx?pid=444



It sounds as if this kitty does have health issues, and needs help. Thank you for reaching out to help him!