I've always believed that only the apostles could give the Spirit by the laying on of hands. A couple of events have me confused though. The first is Saul's conversion (Acts 9). The Lord appeared to Ananias and gave him a message to deliver to Saul. Ananias then placed his hands upon Saul so that he could be filled with the Holy Spirit and Saul's eyesight be restored. Couldn't this make Ananias a 14th (Matthias being the 13th) apostle? Secondly, the events of Philip in Samaria are interesting. Is this the same Philip made an apostle by Jesus (Mark 3)? Why then couldn't he give them the Spirit? We see that he could perform miracles and other signs. Why then did the apostles in Jerusalem send Peter and John afterwards?
These are very good questions. They show you are studying with a view toward learning the truth.
According to Acts 8:18, the Holy Spirit was given only by the laying on of the apostlesí hands. The context, however, shows that this is referring not to the indwelling of the Holy Spirit which comes to everyone when they are immersed for forgiveness of sins (Acts 2:38), but rather to the gifts of the Spirit (the miraculous gifts). Understanding that should help answer your questions.
When Ananias went to Paul he did lay his hands on him. Whether that led to Paul regaining his sight is not clear. What it does say is that Ananias was there so that Paul could receive his sight and be filled with the Holy Spirit. The next verse says that Paul was baptized. That baptism alone would cause him to be filled with the Holy Spirit, in the non-miraculous sense. Paulís subsequent ability to pass on the ability to perform miracles would then have been a result of his being the apostle to the Gentiles, and was probably conferred directly by God during the three years mentioned in Galatians 1:17-18. Viewed this way, Ananias would not have to be an apostle, and there is never any indication that he was one. In fact, all indications are that the apostles, other than Paul, stayed in Jerusalem for years after this (Acts 8:1), and so Ananias would most likely not be an apostle.
The Philip of Acts 8 is probably the same Philip that was most recently mentioned by Luke before that. This would be the same Philip that was chosen in Acts 6:5 to assist with the ministry to the Grecian widows. Thus, he was not the apostle Philip, but another Philip. (This would have been a fairly common name among those of Greek ancestry.) This other Philip (of Acts 6) would have had the ability to perform the miracles, but not the ability to pass it on. It would have made it easier to understand that they were two different people if the apostles that came up from Jerusalem had been Peter and Philip rather than Peter and John, but that didnít happen.
I hope this clears up your confusion.