An entry visa can be issued directly at Lom-Tokoin Airport or at the border for a payment of 15,000 CFA. (US$30)
It may be cheaper to get the visa on arrival than at an embassy but you may have to wait some hours at the airport for the visa.
Visas can be extended easily and for less than ten dollars. You need to drop your passport at an immigration office and pick it up the next day.
Togo information in French - includes embassies and consulates.
If you are travelling to Benin, Burkina Faso, Cote d'ivoire, Niger and Togo you may apply for a Visa Touristique Entente which costs 25000cf (about (US$50). It covers all the above countries, is cheaper and less work than getting single visas for each country.