"I am looking for a striker and if I can get one to supplement the three I have got then I will do," Tisdale told thisisexeter.co.uk.
"I am not prepared to divulge any news at the moment. I have made some enquiries but none yet have come to fruition."
The club's sporting director Julian Tagg has however admitted that Guinan was on a list of potential targets drawn up.
Tisdale added: "We want to improve and keep progressing this squad. We want to get better and get into those play-offs.
"Anyone coming in has to be the right player at the right place. I am always looking for players."
With thanks to Confguide.com