I can't hide the fact that I love visiting different churches. While I sometimes get frustrated by the fragmented nature of Christianity post-1053 AD, I've also found that the diversity allows for what may be lightly called "church tourism." While I believe that when you're home, you should have a home church where you live out your calling and pour everything into, when I'm traveling, I take the opportunity to check out the landscape.
Some principles for visiting churches:
1. Don't judge anything. When going to a new church, it is easy to criticize and in your mind say a lot of "Well, at our church we do this ..." etc, etc. Don't fall into this trap. Every church is different and has a slightly different expression of culture and worship that can be offered to God. Go thinking "I'm going to become part of this place and worship amongst these people." You can give yourself to it and have a great time.
2. Don't be uncomfortable. I think that many people who say a church just wasn't welcoming were likely giving off "uncomfortable" signals. If someone comes into your home and they're frowning, acting like they don't want to talk, and just keep to themselves, it's going to be an awkward visit and those folks might not really want you there after a while. In a church, I think at least on the sociological level, it's the same way. Go in with a smile and shake some hands. People will likely be friendly and want to talk. If you're intentionally friendly and no one returns the favor, then you know something is up, but I don't think that's the case most of the time. Someone wants to say hello to new people in just about every church.
3. Compliment and thank the pastor. Pastors get a lot of flak and critique. In smaller churches, visitors are big deals, and when a visitor says something nice it eases relationship building and allows everyone to get to know each other. Focus on the positive and smile. Pastors are sometimes introverts so they may not naturally come and say hello, but most want to meet you. Don't gauge the pastor by posture, but keep an open stance and let happen what needs to happen.
4. Spend some time in worship. All the evaluation stuff can keep you from remembering that ultimately you are looking for a place of worship -- not just a place to find a best friend. Focus on the Big Guy, pray some, close your eyes and seek Wisdom. Picture Jesus and spend time in His company. I think most folks would enjoy a church more if they realized and practiced actual worship in the church rather than thought about whether they're going to be accepted or not. If you want to find God, He's there. Spend time with Him and let the church be who they are, and let them worship too.
5. go with the flow. All churches have quirks. Learn 'em, and learn to love them. All the grumbling I see in churches tends to be in bad spirit. Rather than grumble, learn the history of the church. Learn why there are so many sections. Experience and understand that generations have come and gone in most churches and there is an abiding love for the spaces created for learning, fellowship, worship and partaking in the sacraments.
I think if you follow some of these guidelines you'll have a great time on vacation going from church to church. Try it out and see. It is quite refreshing. And if you don't have a church home yet, these principles might help you find one.