It's probably not the best habit to get into until you're much further spiritually with the Word, but if it's someone that recently died that you really really miss, I don't think the Old Testament law about saying nothing to the dead applies, particularly when it's someone you're reasonably sure had things right with our Lord. The danger, obviously, is making it a habit with everyone that comes to mind, or even with a single person that comes to mind and getting to where you're expecting replies and then something you DON'T WANT TALKING TO YOU starts trying to imitate them and tell you all kinds of stuff, like it's your fault they're dead, or other total nonsense that you'd likely ordinarily blow off. But when you open that door, you can make yourself vulnerable emotionally and in every other way to deception.
I had a brief visit a day or two ago from someone that used to post on these boards, but died last year. Wasn't looking for the visitation. It was less than a minute. And there's genuinely nothing to pass along to either his friends or family. It was something personal in the way of validating things that I stand for that most of the Body at present would view as truths peculiarly my own. Again, nothing to pass along to anyone else at these boards or to any of his family. I wasn't looking for confirmations of any kind of anything 'cause I already know my chapter and verse that I base stuff on.
I'm only bringing this up right now 'cause this question came up as far as whether that kind of communication is possible. Yeah, it is, but beyond a really, really quick "Lord, tell so and so that I love them, or that I'm sorry about such and such, or that I finally know what you meant by __________, or I'm doing better about______..." I wouldn't generally pursue anything along those lines. But if it's a part of your having peace for the rest of your life that things are resolved between you and someone else, just be brief and then cast the care completely over on the Lord and don't touch it again in your thought life, knowing that you said your

Again, this is mainly to avoid oppressive spirits that would try to move in on you. This is liable to be one of the ways that mediums innocently get started. Something unresolved, but then they just keep pursuing it and keep pursuing it until a demon materializes and says "hi, I'm _________(fill in the blank)."