Beechcraft Baron pilot is concerned by lack of taxiway identifiers at F45.

Narrative

We departed ramp intending to taxi to Runway 8R at F45 (North Palm Beach; FL). We were unable to pick up our IFR clearance on 120.82 and I was preoccupied with getting it; so I didn't have to depart VFR. It is a busy airport with lots of departures; arrivals; and general traffic surrounding it. I had also gotten up early and flown 6 hours already with another 4 hours ahead of me. I was unfamiliar with the area since I mostly fly in the mid-Atlantic area. I was also flying a plane that I don't fly often since my normal plane was down for maintenance. As I was taxiing; I realized that I wasn't taking the proper route to my intended runway; so I took a closer look at the taxi chart and I quickly realized that NONE of the taxiways were marked on my chart! I thought it must have been a mistake. I was using charts printed off computer. Every now and then they print funny and I assumed that is what must have happened. I had the Copilot turn on his 496 and there were no taxiway markings there either! I never noticed that before. I fly to uncontrolled fields often; but never with such complex taxiways and runways that I would need to reference a taxi chart. I ended up headed to Runway 13 so I decided to just depart from there since the winds were calm. There was a lot of traffic coming and going from various runways and I decided that maybe it wasn't such a good idea and that I should taxi back to Runway 8R. Helicopters were using Runway 8L; the turf parallel runway; but I couldn't figure out where that runway was! I saw the signs; but I had no idea that a paved taxiway or even a part of a runway would cross over a turf runway! My mind just would not accept that I was seeing a turf runway despite the hold lines painted on the taxiway. All the while; the Copilot was switching the transmit button back and forth between Communication #1 and Communication #2 both announcing our taxi intentions and trying to get clearance (we thought we might be able to pick it up from different locations on the airport). I am still not certain; but I may have caused a helicopter to go around by taxiing over the turf runway in use while trying to get over to Runway 8R. There were so many planes and helicopters swarming around and at one point we realized that we were transmitting on the wrong radio from all of the switching. There were several things that could have been done to prevent my confusion: break the trip up into 2 days so I wasn't so tired; have another pilot fly (which I tried to do but they didn't want to and the owner of the plane was also a passenger! I was not happy about that); studied the taxi chart better to orient myself and regain my situational awareness; or call for clearance on my phone so that I wasn't so preoccupied with how to get it. I will make a suggestion that taxiways at uncontrolled airports be marked on the chart if they are defined on the surface. For the life of me; I can't understand why they aren't! I also now know that runways and taxiways can and do; in fact; intersect turf runways; and will be more diligent about understanding what I am seeing.