Rule of thumb for new chameleons is 3 days no eating is the norm in many cases. Essentially this is the adjustment period, where they are still recuperating from the trip and learning about their new home, so eating does not happen very much.
All chams are different, my female panther arrived from washington and ate one hour later. My Sambava arrived from Pomona and did not eat for five days. My eldest Sambava also arrived from Washington and ate two days later, as you can see it is all very random and specific to each individual chameleon.
However, as long as the chameleon was well nourished before its journey, then usually they can last up to a week with no food with little to no health concerns.
Try a variety of food : Crickets, Super Worms, Horn Worms, Silk Worms, Roaches - most of which are commonly available on the internet for inexpensive prices. Just make sure to Gutload properly using ( minus silkies and horn worms which have dedicated diet requirements - see hornworm and silk worm chow ) a multitude of dark and leafy greens - romaine and mustards, even endives are great. you should also include Carrots, Potato ( limited ), sprouts, honey, oranges, apple.
Be aware that these need not be just for the chameleons, all gutloads are integral parts of human diets as well. Many people make the mistake of for say buying carrots just for the crickets. In reality it is much for effective to buy carrots for your family - and after washing the carrot, it is usually peeled. Those peelings are usually thrown out, however they are perfect for your feeders.
The same applies to the end of your lettuce heads. Even left overs are suitable, as long as nothing pervaded it, such as salad dressing or sauces.
When it comes down to that method, feeding your feeders can remain relatively inexpensive.