I would not advice name and shame as usually this lead to a confrontation of some sort but offer some ideas of how I have previously handled similar .
1. Add late payment charges to all invoices
2. add additional payment charges for chase up letters (just like banks)
3. Ensure you keep all documentation, letters, e mails
4. Keep records of all tel calls
When all this fails then the cheapest option is the on line small claims court
https://www.moneyclaim.gov.uk/csmco2/index.jsp
5. Also take a copy of the claim form before you send it,Write DRAFT across it and send it to the person/company with a covering letter stating your intention to send to court if no payment+charges made within x number of days.
I also did this with a very large football club and they paid in hours
This allows a simple option but you need their address to send the on line papers and costs about £35 but this gets added to the charges. If the person/company fails to pay then a court order is done and this effectively 'screws up' the person/company from obtaining credit and it also keeps it lawful and allows you do show credibility and business accumen Hope this Helps Ian