Welcome to the forum, Joe and welcome back to the hobby. We have plenty of members from abroad that may be able to help you with a retailer. As far as information these links will help get you started on building your vivarium
http://www.frogforum.net/vivarium-te...struction.html
New England Herpetoculture LLC - Vivarium Construction 101
New England Herpetoculture LLC - 10 Commandments of Vivarium Building
the NE Herp link will show you plants that are acceptable in a terrarium as well as other acceptable items.
As far as cleaning, a good misting should push all the fecal matter to the soil. Establishing microfauna, springtails and isopods will help keep the tank clean and soil fertilized naturally. They will also provide a snack for your amphibian between regular feedings. They're easy to culture and maintain.
New England Herpetoculture LLC - Springtail Care
i keep my isopods in a mixture of ABG and crushed leaf litter with card board on top and feed them rapashy bug burger. I mist them as necessary. Repashy Superfoods :: RETAIL SALES :: By Product Name :: Bug Burger - Repashy Ventures - Distributor Center
A misting system is a nice thing to have but not a requirement. I maintain my vivariums by misting with a spray bottle and dechlorinated water. It cost me 98 cents at a home improvement store vs the 50 dollars /roughly £125 for the fogger and 100 dollars / roughly £250 for most misting systems. If you maintain lots of vivariums or if you have expendable money then the investment is worth it. They're great to have but not necessary.
Give your vivarium about a month to establish ( microfauna to establish and plants to take strong root) before adding frogs. Take that time to measure your humidity levels and average temperature levels to ensure everything is right. Building a vivarium is very rewarding and is not just for experienced keepers. An educated beginner will have great success as long as you don't rush the process. Utilize the forum's search feature and many questions will be answered. Again welcome and best of luck.