A lot of inspiration comes from listening to the work of others, and a lot of creativity comes from trying out the DX and VST plugins, and indeed experimenting with the plgins that come in Audition.
Most effects work when they are short, just one word or phrase for example. The purpose is to make a statement or word, name stand out, like making a line of text italic or bold; if you made all the text italic or bold or 3D then it doesn't work as an effect, but if you make the heading or the logo 3D then that is a deliberate standout effect. This is how effects are used in radio imaging anyway. If you're making a movie and you want to place a person in a cave or a church, then all of his dialogue will be echoed. This is a different use of effects. Radio imaging has become like a showcase of 3 or 4 different effects, the attitude is grunge, it's a mashup, like you're screwing up the boring old straight read as badly as possible to sound rebellious, and therefore cool for young people.
It's also clever if you match the effects to what is being said, for example:
HAPPY FM (effect: a repeating stutter on the 'H' in happy)
PLAYS TODAY'S BIGGEST HITS (effect: big reverb or stretch effect on the word 'biggest')
AND THE GREATEST MEMORIES (effect: an old AM radio/telephone effect on this statement)
....amd wooshes and zaps between each statement!
These are just obvious and common effects, and the above only lasts about 3 seconds! The pieces are made seprately and then you get some beats and beatmatch the pieces. Masters of this type of production like Emmet and Marty have developed some really crazy-sounding creativity like this over the years, and it's very impressive. YOU have to experiment and experiment .. and post some here