While the Detroit Lions have a prime pick in the 2013 NFL Draft, they will assuredly be busy in free agency as well, especially since they have so many of their own free agents to deal with. Defense will likely be the primary focus for the Lions, but they may look to add some free agents on offense as well. Here's some players the Lions might target as free agents on offense.
I think the only places the Lions really need to address with free agents on offense are wide receiver and running back. Of course, Jeff Backus and Gosder Cherilus may not be back, and if that is the case the offensive line will be a definite issue, but that remains to be seen. What is certain is that Detroit will need to improve at wide receiver, and probably at running back. This is even presuming they bring back Joique Bell, a restricted free agent. This is also not presuming Jahvid Best will be back. They have to expect not to have him.
One thing is for certain, if the Lions spend a pick before the first round on a receiver or running back, I will be annoyed. They foolishly spent several early picks on running backs and receivers recently. The depth in the Draft for both those positions is so high, and they are the most fungible positions, running backs particularly. Think of how many good backs and receivers were late picks, or free agent signees like Bell. The number is much higher than for other positions. Unless you are getting an elite wide receiver or running back, don't take one in the first round. If they aren't a really good prospect, don't even bother in the second or third round.
However, this is about free agents. When it comes to running back, they could possibly use another big play back, a la Bell (or Best), but they could also use another big back potentially to go along with Mikel Leshoure. Regardless, this will be a running back rotation, so they don't need to spend much money.
For a speed guy, the top choice for me would be Justin Forsett. You may remember Forsett from the Thanksgiving Day game against the Texans. He had a long touchdown run that was in no way controversial. Danny Woodhead would be nice, as he is a really good receiver out of the backfield. LaRod Stephens-Howling or Tashard Choice could do in a pinch.
For bigger backs, they could bring in a veteran on their last legs like Rashard Mendenhall. A couple of former Jaguars interest me in Rashad Jennings and Greg Jones. They could also bring in former Michigan State Spartan Javon Ringer.
As for wide receivers, Nate Burleson and Ryan Broyles are both coming off injury, and Broyles won't likely be ready when the season begins. What they need most is a smaller, possession type receiver. Again, there's no need to spend big money here. Danny Amendola would be nice, but will likely be a bit pricey. Julian Edelman likely won't get out of New England, but would be worth a shot. Honestly, the pickings are a bit slim. Ramses Barden would be worth a shot, even if he's a big guy as opposed to a slot receiver.
I'm a bit concerned about these wide receivers options, but the Lions should be able to add a running back cheap. Maybe Detroit should spend a sixth round pick on a possession type receiver. It's unlikely they will pan out, but it's worth a shot.